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WYOMING GEMSTONES & ORNAMENTAL STONES

INTRODUCTION

Because of beauty and quality, some minerals are valuable as gemstones. The term gemstone is applied to minerals that are sufficiently attractive to be used for personal adornment after they are cut and polished (Hurlbut and Switzer, 1979). Modifiers such as precious and semi-precious have been used to distinguish the more valuable from the less valuable gems. These terms are considered synonymous with the terms gem and near-gem which are dependent on the economics of market conditions. For instance, near-gems can be considered low-quality gemstones in a favorable market. In less favorable markets, the same stone may have no value as a gemstone.

Collectable minerals are minerals that have intrinsic value as a specimen. Some collectibles are unique because of crystallinity, rarity, or size. Most collectibles have little value as a gemstone, but still have value to a collector.

Ornamental stones are minerals and rocks of extraordinary beauty that may be valuable as a cut stone, an uncut stone, or a polished slab or cabochon (Figure 1, 1a, 1b). These can be as attractive as any high-quality gemstone.

Wyoming has several deposits of high-quality minerals that are considered as potential sources of gemstones, semi-precious gemstones, collectibles, and ornamental stones (Figure 2). Some of these include jade, ruby, sapphire, diamond, aquamarine, peridot, agate, jasper, and others. The precious metals - gold, platinum, palladium and silver are also found in Wyoming, and some are considered to have value as a precious metal, jewelry, ornamental stones, and/or as collectibles. An excellent book on Wyoming’s precious and unique mineral and rock occurrences was published by the Wyoming State Geological Survey in 2000 - “Gemstones and Other Unique Minerals and Rocks of Wyoming - a Field Guide for Collectors”, and written by two field geologists with considerable experience in minerals and rocks - W. Dan Hausel and Wayne Sutherland. This 268-page guidebook provides information on more than a hundred sites in the state where one might find interesting gems and other unique minerals and rocks.

WYOMING GEMS & MINERALS

Nearly every year, a previously unreported mineral is identified, or an extraordinary specimen is found in the State. Just a few years ago, a 7.5 ounce gold nugget was found by a coin hunter at South Pass near the southern tip of the Wind River Mountains (Figure 3). Private collectors found two other attractive minerals in western Wyoming – variscite and minyulite (Figure 4). More than 25 years ago, diamonds were accidentally discovered in Wyoming (Figure 5), and within the past few years, some peridot, ruby, sapphire, and iolite were discovered in the Cowboy State by the WSGS.

PERIDOT

Prior to 1998, peridot was unknown in Wyoming. However, a diamond research project by the WSGS, led to the discovery of gem-quality olivine (peridot) in the Leucite Hills north of Rock Springs (Figure 6). During field investigations, W. Dan Hausel recognized the potential gemstone and collected material from two anthills. The anthills were processed for olivine and diamonds. No diamonds were recovered, however, more than 13,000 carats of peridot and industrial olivine were extracted. A large percentage of the material is of potential gem-quality (Figure 7a, b, c, d, e, f , g). Larger material can be expected in the soils adjacent to Black Rock as well as from the Black Rock lamproite. Black Rock itself contains xenocrysts of transparent olivine as large as 0.25 to 0.5 inches in diameter.

RUBY – SAPPHIRE - IOLITE - KYANITE

Corundum has been known in the State for many years, and scattered reports allude to periodic findings of gem-quality corundum. The most significant find, to date, was made by W. Dan Hausel of the WSGS in Palmer Canyon of the Laramie Mountains west of Wheatland prior to 1998. Several specimens of facet grade corundum (sapphire) (Figure 8) were collected during the investigation of the deposit. The corundum occurs in vermiculite schist, gneiss, and mica schist. Some samples of the vermiculite schist contain as much as 20% corundum!

Not far from the corundum schist is a beautiful rock known as kyanite schist. This rock forms spectacular outcrops with hundreds of light-blue kyanite prisms with occasional pink, pinkish-purple and white sapphires (Figure 9, 9a).

Another significant discovery made by the WSGS was of transparent cordierite in the Palmer Canyon deposit. A significant percentage of the cordierite is gem quality. Gemstones manufactured from transparent cordierite are known as iolite. The iolite at Palmer Canyon includes some very high quality material. The gemstone (Figure 10) is found in gneiss as grains and nodules. Some rock specimens recovered by the WSGS contain as much as 25% gem-quality cordierite. Other deposits of iolite are reported in the central Laramie Range that are currently under investigation by the WSGS.

Spectacular specimens of transparent to translucent cordierite collected during the initial investigation of the property weighed 1.5, 6, 11.5, 13.5, 14, 63.5, 109.5, 308.5, 887, as well as extraordinary specimens of 1,715 and 2,948 carats. Other samples recently collected from the property included a group of large gem-quality nodules that are facet-grade. One of these is a beautiful, violet-blue, massive, transparent cordierite (>3000 carats) measuring 4.25 x 2.5 x 1.25 inches (Figure 11). More than 10,000 carats of gem-quality material have so far been collected from the property by the WSGS simply by using a rock hammer. This deposit could potentially become a significant source for both gemstones and ornamental stone (Figure 12a, b, c, d, e).

The cordierite found on the property has been categorized as: (1) violet to blue, transparent cordierite (iolite) (Figure 13a, b, c), (2) dark-gray transparent to translucent cordierite, some with distinctive parting (Figure 14a, b, c, d), and (3) translucent to cloudy cordierite with distinctive parting. These have little value as gems; however, some of the poor-quality cordierite was faceted producing some surprisingly attractive jewelry (Figure 12b).

Since our (WSGS) initial discovery, we have investigated other iolite deposits in the central Laramie Range that are hosted by Proterozoic anorthosite and Archean gneiss, serpentinite and metapelite and are located south of Palmer Canyon. One of these lies within a very steep and rugged canyon (Figure 14e) that is nearly inaccessible. Even so, this deposit is much more impressive than the Palmer Canyon discovery and some very spectacular material was identified during our initial reconnaissance of this deposit in 2004. The first specimens collected from this area included high-quality kyanite (Figure 14f, 14g), the largest iolite gemstones in the world (Figure 14h, 14i, 14j), and minor amounts of ruby. The geology of this entire region is very favorable for gemstones and we anticipate several additional discoveries in this region.

Due to the successful research by the Metals and Precious Stones Section of the WSGS and to the several gem discoveries made by W. Dan Hausel and Wayne M. Sutherland, Wyoming could potentially become a source for a variety of high-quality gemstones that were previously unknown in this region. For instance, numerous iolite, ruby, sapphire and kyanite gemstones have now been cut from material collected in the central Laramie Range, and other gems including diamond, peridot, cape rubies (pyrope), chromian diopside, aquamarine, precious beryl, and others found scattered around Wyoming have also been faceted and are now all recognized in this State. Some of the gems from the central Laramie Range deposits are quite spectacular (Figure 14k, 14l, 14m,14n, 14o, 14p,14q, 14r, 14s,14t,14u,14v,14w,14x,14y,14z). We would like to thank Vic Norris for loaning us some of these specimens to photograph.

Prior to this discovery of the Palmer Canyon gemstones, the WSGS mapped another corundum deposit in the Granite Mountains in the central part of the State near Jeffrey City. Some corundum specimens as large as 2.5 inches across were found in quartzofeldspathic gneiss and in chlorite schist at this deposit that was mapped over a strike length of 5,000 feet (Figure 15). The unique corundum at what is now referred to as the Red Dwarf deposit includes reddish purple rubies (Figure 16) that produce some attractive cabochons (Figure 17).

Much of the corundum from the Red Dwarf deposit is encased in a reaction rim of fuchsite. One specimen of a fuchsite pseudomorph after corundum (with minor preserved corundum) was found several years ago by J.D. Love of the US Geological Survey. The specimen, given to the WSGS, is 5 inches long and 3 inches in diameter. It provides a barometer of what can be expected as far as size of stones. Nearby, an outcrop of serpentinite identified by Robert Odell, locally contains sapphire.

Since the investigation of these two corundum deposits, the WSGS has explored a group of corundum occurrences found elsewhere in the state. A significant percentage of the occurrences occur in vermiculite schist.

JADE

Wyoming is known as the Jade State. Nephrite jade, also referred to as Wyoming jade, was discovered in Wyoming in the early part of the 20th century (Figure 18). Some jade found in Wyoming was as high of quality as any jade in the world (Figure 19, 19a, 19b, 19c, 19d, 19e). Jade is hard and tough and includes black opaque specimens and beautiful translucent to transparent apple green specimens. Additionally, some jade is white, and other specimens of jade have included a variety of green shades. Some very attractive jewelry (Figure 20) and carvings (Figure 21) have been produced from Wyoming jade.

The green color in nephrite jade is the result of iron within the crystal lattice. When iron is absent, the mineral is practically colorless to cloudy white, resulting in a variety known as ‘muttonfat jade’. Other varieties of Wyoming jade include translucent, emerald-green ‘imperial jade’; ‘apple- green’ jade, ‘olive-green’ jade, ‘leaf-green‘ jade, ‘black‘ jade, and ‘snowflake’ (mottled) jade (Bauer, 1968). The greater commercial values are attached to the lighter green, translucent varieties.

Individual pieces of detrital jade can vary in appearance. Some pieces may be covered with a cream to reddish-brown weathered rind that hides the characteristic color of the jade. But where naturally polished with a high-gloss waxy surface, known as 'slicks', the jade is recognizable.

Jade never shows external structure, except where the mineral pseudomorphs the habit of another mineral. For instance, in the Granite Mountains of central Wyoming, nephrite pseudomorphing quartz has been found with pseudohexagonal habit (Figure 22). Typically, nephrite occurs in irregular masses and lacks cleavage.

Several large boulders have been found in Wyoming. The largest was a 14,000 pound boulder of low-quality black jade reportedly found in the Prospect at the southern end of the Wind River Mountains (Hemrick, 1975). Some spectacular specimens of green jade have been found in the central part of the State in the Granite Mountains and Crooks Gap regions near Jeffrey City.

GOLD

Wyoming has become the favorite place for many gold prospectors and treasure hunters. Over the past 20 years, the WSGS identified and discovered several gold deposits and occurrences in the state, and even discovered a whole new gold district in 1981 known as the Rattlesnake Hills. These discoveries have provided new prospecting sites, not only for mining companies, but also for prospectors and treasure hunters.

Gold can be panned from many streams in Wyoming. For example, in 1993 and 1994, the WSGS panned gold from several drainages along the northern flank of the Medicine Bow Mountains. Many of the gold-bearing drainages occurred along I-80 near Arlington. As incredible as it may seem, Eric Nielsen, a contract geologist for the WSGS, even found gold in the Laramie landfill!

Prospectors, collectors, and treasure hunters tend to search drainages in known gold districts, as well as old mine dumps. Two of the more popular districts are South Pass in the Wind River Mountains, and Douglas Creek in the Medicine Bow Mountains (Figure 23). In recent years, treasure hunters have found several hundred gold nuggets in these and other regions (Figure 24). South Pass has especially been productive. One treasure hunter found more than 100 good-sized nuggets in recent years, and another treasure hunter found a 7.5 ounce gold nugget that is about the size of a small hens egg. The WSGS commonly leads geological field trips to this area, and on nearly every field trip, someone finds a nice gold specimen (Figure 25).

Some good areas are often overlooked. For instance, one treasure hunter reported finding 299 nuggets in the Encampment district of the Sierra Madre using a metal detector. This is an area known for copper, and few people think of gold when they think about the Sierra Madre. Another area that has produced several nuggets in the past is the Mineral Hill district in the Black Hills of northeastern Wyoming. Many other areas may also be productive for treasure hunters, and we recommend contacting the WSGS for specific information.

DIAMOND-PYROPE-CHROMIAN DIOPSIDE

A few decades ago, in 1975, diamonds were accidentally discovered in kimberlite in southeastern Wyoming south of Laramie (McCallum and Mabarak, 1976). Since 1975, more than 130,000 diamonds have been recovered from the Colorado-Wyoming State Line district south of Laramie. The diamonds have included gems weighing more than 28 carats (Figure 26). Several diamonds have also been found in Wyoming (Hausel, 1998d). About 30 to 50% of the diamonds from Wyoming and Colorado have been gemstones.

Two octahedral, gem-quality diamonds were also found by a prospector (Paul Boden) in Cortez Creek in the Medicine Bow Mountains several years ago (Figure 27). This is an area that had been previously overlooked for diamond.

Many of the diamonds found in Wyoming and Colorado have come from kimberlite pipes (Figure 28a, b). These unusual pipes contain some semi-precious stones and many rare mantle nodules and very attractive specimens of decorative stone in addition to diamond. The semi-precious stones recovered from the pipes include transparent to translucent blood red, violet and orange yellow pyrope garnet, almandine garnet and some emerald green chromian diopside and chromian enstatite (Figure 29). A significant percentage of this material is also gem quality (Figure 30a, b, c, d, e, f, g, h).

JASPER & AGATE

When rock hounds talk about jasper and agate, they almost always talk about Wyoming. Wyoming has produced many kinds and types of agates, jaspers, and petrified wood (Figure 31). In one location in the Rattlesnake Hills west of Casper, the WSGS recently identified a deposit of essentially untouched massive red and tawny jasper covering a surface area of a few acres. Some agates from Wyoming are indigenous to the state, and form spectacular specimens. Few agates can match the beauty of the rare Youngite agate from the Hartville uplift in eastern Wyoming (Figure 32a) and few are as attractive as the Sweetwater agates (Figure 32b) from the Jeffrey City area in central Wyoming.

OPAL

SUMMARY

We have only presented a few of the interesting rocks and minerals that are found in Wyoming. For example, Wyoming has some well-formed garnets (Figure 33), beryl (Figure 34), orbicular granodiorite (Figure 35), attractive labradorite with excellent ‘fire’ (Figure 36) as well as many other minerals, rocks, and gemstones.

Many other minerals including opal, aquamarine, amber, barite, etc are found in Wyoming. The WSGS welcomes inquiries related to minerals and rocks in Wyoming. Please feel free to contact us (dhause@uwyo.edu) and we’ll do our best to help you. We look forward to hearing from you and crossing paths in the field.

SOURCES USED TO COMPILE THIS ARTICLE

Bauer, M., 1968, Precious Stones, Volumes 1 & 2: Dover Publications, Inc, New York, p. 1-627.

Hemrich, G.I., 1975, The Game Warden's jade: Gems & Minerals, no. 457, p. 8-15.

Hausel, W.D., and Sutherland, W.M., 2000, Gemstones and other unique minerals and rocks of Wyoming - a field guide for collectors: Wyoming State Geological Survey Bulletin 71, 268 p.

Hausel, W.D., 1999, Quartz and chalcedony in Wyoming: International California Mining Journal, v. 68, no. 10, p. 38-43.

Hausel, W.D., 1998, Diamonds and mantle source rocks in the Wyoming Craton, with a discussion of other US occurrences: Wyoming State Geological Survey Report of Investigations 53, 93 p.

Hausel, W.D., 1996, Wyoming nuggets: International California Mining Journal, V. 66, no. 4, p. 7-12.

Hausel, W.D., 1997, The geology of Wyoming's copper, lead, zinc, molybdenum, and associated metal deposits in Wyoming: Geological Survey of Wyoming Bulletin 70, 224 p.

Hausel, W.D., 1996, Economic geology of the Rattlesnake Hills supracrustal belt, Natrona County, Wyoming: Geological Survey of Wyoming Report of Investigations 52, 28 p.

Hausel, W.D., 1993, Guide to the geology, mining districts, and ghost towns of the Medicine Bow Mountains including the Snowy Range scenic highway: Geological Survey of Wyoming, Public Information Circular 32, 53 p.

Hausel, W.D., 1991, Economic geology of the South Pass granite-greenstone belt, Wind River Mountains, western Wyoming: Geological Survey of Wyoming Report of Investigations 44, 129 p.

Hausel, W.D., 1989, The geology of Wyoming's precious metal lode and placer deposits: Geological Survey of Wyoming Bulletin 68, 248 p.

Hausel, W.D., 1986, Minerals and rocks of Wyoming: Geological Survey of Wyoming Bulletin 66, 117 p.

Hurlbut, C.S., Jr., and Switzer, G.S., 1979, Gemology: John Wiley and Sons, New York, 243 p.

McCallum, M.E., and Mabarak, C.D., 1976, Diamond in State Line kimberlite diatremes, Albany County, Wyoming, and Larimer County, Colorado: Geological Survey of Wyoming Report of Investigations 12, 36 p.

Figures

Figure 1: Very attractive sterling silver bracelet with epidotized granite from the Big Horn Mountains of northern Wyoming (photo courtesy of Robert Bratton).

Figure 1a: Large (20.98 ct) Sweetwater agate surrounded by (starting at left top in clockwise direction), specular hematite (7.73 cts) from the Charter Oak Mine, Encampment, specular hematite from Hartville (7.08 cts), jasperoid (6.06 cts) from Aspen Mountain near Rock Springs, banded iron (10.3 cts) from Copper Mountain, fuchsitic quartzite (7.25 cts) from Copper Mountain, and jasper (8.17 cts) from the Hartville area (photo by W.D. Hausel).

Figure 1b: A light blue apatite (0.39 ct) cab fashioned from a material collected in the Granite Mountains north of Jeffrey City (photo by W.D. Hausel).

Figure 2: A collection of minerals and rocks from Wyoming (photo by W.D. Hausel)

Figure 3: A 7.5 ounce gold nugget recently found at South Pass (photo by Dave Freeman).

Figure 4: A slab of minyulite discovered by Robert Bratton in western Wyoming. (Photo courtesy of Robert Bratton).

Figure 5: Gem and industrial diamonds recovered from kimberlite in the State Line district, south of Laramie (photo by Karl Albert).

Figure 6: Peridot collected from anthills in the Leucite Hills (photo by W.D. Hausel).

Figure 7a: Faceted peridot (0.12 carat) from the Leucite Hills anthills.

Figure 7b: Princess cut (0.11 carat) peridot from the Leucite Hills anthills.

Figure 7c: Princess cut peridot gemstone from the Leucite Hills near Rock Springs.

Figure 7d: Faceted peridot (1.5 cts) found in the Leucite Hills near Rock Springs. The peridot shows excellent transparency and color in transmitted light (photo by W.D. Hausel).

Figure 7e: Same faceted peridot (in reflected light) (see Figure 7d), surrounded by uncut gem-quality olivine from the same locality. More than 13,000 carats of gem material were recovered by the WSGS from just two anthills in the Leucite Hills!

Figure 7f, g: Selection of faceted Wyoming peridots collected from anthills in the Leucite Hills north of Rock Springs (photos by Robert Gregory).

Figure 8: Palmer Canyon gemstones. The gemstone in the middle is a nearly flawless 1.1-carat pinkish-purple sapphire. The cabochon in the upper right of the photo is a semi-precious 1.4-carat pinkish-brown sapphire (photo by W.D. Hausel). The gemstones were provided to the WSGS to photograph by Vic Norris of Lyons, Colorado.

Figure 9: Spectacular boulder of kyanite schist found near the main corundum deposit at Palmer Canyon. Note the hundreds of kyanite prisms exposed on the rock surface. Map board for scale (photo by W.D. Hausel).

Figure 9a: Pink corundum (sapphire - 0.12 & 1.5 cts) and blue kyanite (0.74 & 1.21 cts) from Palmer Canyon (photo by W.D. Hausel).

Figure 10: Sapphires surrounded by iolite fashioned from minerals collected at Palmer Canyon. The transparent iolite gems weigh 0.5, 1.0 and 1.49 carats. These sit next to some translucent to opaque ornamental cordierite that weighs 3.4 and 3.9 carats. Specimens courtesy of Vic Norris (photo by W.D. Hausel).

Figure 11: Three Wyoming iolites sit adjacent to large (>3000 carat) transparent, light to dark-blue cordierite nodule (photo by W.D. Hausel).

Figure 12a: The iolites (0.36-1.33 ct) and sapphires (1.15 and 1.47 ct) shown here are from Palmer Canyon. Courtesy of Vic Norris; photo by Maha Tannous, courtesy of GIA (Gemological Institute of America).

Figure 12b: 3.9 ct Palmer Canyon cordierite necklace (photo courtesy of Chuck Mabarak).

Figure 12c: Faceted Palmer Canyon iolite necklace (photo courtesy of Chuck Mabarak).

Figure 12d: 1.1 ct Palmer Canyon pink sapphire necklace (photo courtesy of Chuck Mabarak).

Figure 12e: Faceted Palmer Canyon red sapphire necklace (photo courtesy of Chuck Mabarak).

Figure 13a: High-quality iolite gems from Palmer Canyon (photo by Robert Gregory).

Figure 13b: Sapphire-blue iolite gems from Palmer Canyon (photo by Robert Gregory).

Figure 13c: Princess cut 0.21-carat Palmer Canyon iolite (photo by Robert Gregory).

Figure 14a: 1.86 carat black iolite cabochon, Palmer Canyon (photo by Robert Gregory).

Figure 14b: 3.02 carat black cordierite cabochon with visible parting (photo by Robert Gregory).

Figure 14c: 2.51 carat black iolite cabochon, Palmer Canyon (photo by Robert Gregory).

Figure 14d: 2 carat black iolite cabochon with visible parting and cleavage, Palmer Canyon (photo by Robert Gregory).

Figure 14e: Wayne Sutherland descends into steep canyon in search for gemstones (photo by W. Dan Hausel).

Figure 14f: W. Dan Hausel stands next to boulder composed of nearly solid, gem-quality kyanite at Grizzly Creek (photo by Wayne Sutherland).

Figure 14g: Specimens of sky-blue gem-quality kyanite collected at Grizzly Creek (photo by W. Dan Hausel).

Figure 14h: The largest specimen of rough iolite in the world recovered by W. Dan Hausel. This specimen weighs an incredible 24,100 carats (10.6 pounds) and potentially contains $1 million in cuttable gems based on the lowest price for faceted iolite (photo by W. Dan Hausel).

Figure 14i: Larger gemstones remain in situ on the outcrop such as this iron-stained iolite (photo by W. Dan Hausel).

Figure 14j: This outcrop shows the enormity of the giant gemstones that remain in situ. This outcrop is nearly solid iolite gem material intruded by a small milky quartz-vein. The outcrop contains potential specimens of iolite of several hundred thousands of carats of high quality material (photo by W. Dan Hausel).

Figure 14k: Translucent pinkish red ruby (1+ carat) from the central Laramie Range (photo by Robert Gregory, specimen courtesy of Vic Norris).

Figure 14l: Group of iolites (4 to 6 carats each) from the central Laramie Range (photo by Robert Gregory, specimen courtesy of Vic Norris).

Figure 14m: Black faceted iolites from the central Laramie Range (photo by Robert Gregory, specimen courtesy of Vic Norris).

Figure 14n: Gem-quality kyanite from central Laramie Range (photo by W. Dan Hausel, WSGS specimen).

Figure 14o: Group of faceted iolites, rubies and sapphires from the central Laramie Range (photo by Robert Gregory, specimens courtesy of Vic Norris).

Figure 14p: Group of faceted iolites, rubies and sapphires next to tweezers scale from the central Laramie Range (photo by W. Dan Hausel, specimens courtesy of Vic Norris).

Figure 14q: Group of faceted iolites and sapphire from the central Laramie Range (photo by Robert Gregory, specimens courtesy of Vic Norris).

Figure 14r: Faceted iolite from the central Laramie Range showing evidence of shearing (photo by Robert Gregory, specimens courtesy of Vic Norris).

Figure 14s: High-quality sapphire from the central Laramie Range (photo by Robert Gregory, specimens courtesy of Vic Norris).

Figure 14t: Large pink sapphire rough from the central Laramie Range (photo by Robert Gregory, specimens courtesy of Vic Norris).

Figure 14u: Close up of a >1.0 carat ruby from Palmer Canyon. Note the distinct cleavage in this specimen (photo by Robert. Gregory).

Figure 14v: A group of 4 to 6 carat iolites from Palmer Canyon (photo by Robert. Gregory).

Figure 14w: Two flawless iolites (< 1.0 carat each) from Palmer Canyon (photo by Robert. Gregory).

Figure 14x: More than 100 carats of excellent multi-color cabochon kyanites from Palmer Canyon (photo courtesy of Vic Norris).

Figure 14y: A group of rubies, iolites and one excellent oriental sapphire from Palmer Canyon (photo by Robert. Gregory).

Figure 14z: A group of iolite (water sapphire) gemstones with one oriental sapphire from Palmer Canyon (photo by Robert. Gregory).

Figure 15: Hexagonal, reddish purple corundum prism collected from the Red Dwarf ruby deposit by Eric Hausel (photo by Robert Odell).

Figure 16: Ruby cabochons fashioned from corundum from the Red Dwarf ruby deposit in the Granite Mountains (photograph by Robert Odell).

Figure 17: 2.77-carat cabochon cut from a Red Dwarf ruby deposit, Granite Mountains (photo by Robert Gregory).

Figure 18: Priceless 218 pound boulder of apple green jade presented to the WSGS by (from left to right) Dave Freeman, Joan and Jack Cuthbertson, J. David Love, and Jane M. Love (photo by Ray Harris).

Figure 19: Translucent apple-green jade from Wyoming (photo by Dave Freeman).

Figure 19a: Apple green jade from central Wyoming (photo by W. Dan Hausel, specimen courtesy of Jay Sundberg).

Figure 19b: Black jade from central Wyoming (photo by W. Dan Hausel, specimen courtesy of Jay Sundberg).

Figure 19c: Black jade from central Wyoming (photo by W. Dan Hausel, specimen courtesy of Jay Sundberg).

Figure 19d: Snowflake jade cabochon from central Wyoming (photo by W. Dan Hausel, specimen courtesy of Jay Sundberg).

Figure 19e: Apple green jade from central Wyoming (photo by W. Dan Hausel, specimen courtesy of Jay Sundberg).

Figure 20: Jade cabochons mounted in rings set against a background of a priceless jade boulder (photo by Ray E. Harris).

Figure 21: Attractive carvings cut from Wyoming jade (photo by Dave Freeman).

Figure 22: Specimens of hexagonal jade pseudomorphs after quartz. These specimens of jade have retained the original crystal habit of the former quartz (Photo by W.D. Hausel).

Figure 23: Gold panners prospecting the Mother Lode in the Medicine Bow Mountains on a 2001 WSGS sponsored field trip (Photo by Ray Harris).

Figure 24: Gold recovered from South Pass (photo by W.D. Hausel).

Figure 25: Quartz pebble with visible found on WSGS sponsored field trip to South Pass (photo by Rattlesnake Jim).

Figure 26: Very nice, 14.2 carat, flawless, diamond octahedron from the Kelsey Lake diamond mine, Colorado. The mine has produced several beautiful specimens including two gem-quality diamonds that weighed more than 28 carats (photo courtesy of Howard Coopersmith and the Kelsey Lake Diamond Mine).

Figure 27: Two octahedrons found by Paul Boden in the Medicine Bow Mountains in 1977 (photo by W.D. Hausel).

Figure 28a: Sloan 5 kimberlite, Colorado-Wyoming State Line district, as seen from the air. The pipe is outline by the open park (treeless area).

Figure 28b: Exposed kimberlite (blue) in the highwall of the Kelsey Lake diamond mine (photos by W.D. Hausel).

Figure 29: Gem-quality red pyrope garnet and emerald-green chromian diopside found in anthills in the Cedar Mountain area (photo by Richard Kucera).

Figure 30a: Beautiful, chromian pyrope garnet (0.07 carat) collected from an anthill at Butcherknife Draw in the Greater Green River Basin, southeastern Wyoming (photo by Robert Gregory).

Figure 30b: Side view of pyrope garnet (photo by Robert Gregory).

Figure 30c: Chromian pyrope (0.06 carat) faceted from anthill material collected at Butcherknife Draw (photo by Robert Gregory).

Figure 30d: Faceted 0.05-carat almandine garnet from a Butcherknife Draw anthill (photo by Robert Gregory).

Figure 30e: Emerald-colored chromian diopside (0.5 carat) surrounded by faceted pyrope garnets collected from anthills in the Green River Basin (photo by W.D. Hausel).

Figure 30f: Chrome diopside collected from a Green River Basin anthill and faceted into a near-gem (photo by Robert Gregory).

Figure 30g, h: Two pyrope garnets faceted from anthill material collected near Butcherknife Draw in the Green River Basin south of Green River. Note the two different colors typical of these garnets (photos by Robert Gregory).

Figure 31: Blue forest petrified wood from the Eden Valley region north of Rock Springs.

Figure 32a: Youngite agatized breccia from Hartville. Specimen courtesy of Norma Beers (photo by W.D. Hausel).

Figure 32b: Sweetwater agates collected by J.D. Love.

Figure 32c: Several Wyoming opal cabochons found in the Beaver Rim region sit between two boulders with raw opal.

Figure 32d: Approximately 170 carats of common opal fashioned from material in central Wyoming (photo by W.D. Hausel).

Figure 33: Large, dodecahedral, chlorite porphyroblast after almandine garnet from the Sierra Madre (photo by W.D. Hausel).

Figure 34: Hexagonal, translucent to opaque, beryl crystal collected from Casper Mountain (photo by W.D. Hausel).

Figure 35: Orbicular granodiorite from the Ferris Mountains (photo by W.D. Hausel).

Figure 36: Labradorite feldspar with excellent fire collected from Sybille Canyon in the central Laramie Mountains. Specimen courtesy of Norma Beers (photo by Wayne Sutherland).