BLUE AMBER - a Total Surprise !

Typical rough Amber pieces from the Baltic

Amber, that strange material that hardened from several species of tree resins from several hundred million years ago. The best known Amber is from the Baltic Region, but it also comes from Africa, the Arabian Peninsula, North and South America and some Islands in the Caribbean. But do not confuse Amber with Copal, Copal is the new kid on the block being only a few million years old and in most cases much softer, coming from Columbia and a few Caribbean Islands.

Piece of Dominican Blue Amber as seen in the rough

Amber is supposed to be amber color, right? Not exactly. There is the original colors of Amber, yellow, orange, honey, cognac or similar. A new delight among jewelry designers is Butterscotch Amber, found in the Baltic as well as the Middle East. But there also is cream, cherry, red, green and even blue, which is by far the rarest of all the Ambers. Up to this day many people do not believe in the existence of "BLUE" amber. Must be something in the air or in the ground, since two of the more highly prised gemstones that come from the Dominican Republic are both "BLUE" - Blue Amber and Larimar.

Chunk of Dominican Amber with Reds-Cognac-Yellow coloring.

Is Blue Amber Truly Blue? No. It is not. And yet, it is. Confused? Blue Amber is a result of fluorescence and no solid color exists. Ultra-violet or violet light is re-emitted as blue or green light, attributed to the presence of poly-nuclear aromatic molecules. Therefore, Blue amber is blue, but not the way you might think.

When sunlight strikes the Blue Amber on a white surface the light particles pass right through and are refracted by the white surface. Result: the Blue amber looks almost like any other Amber, only with a light blue hue. But when the light particles can't pass through and refract back, the hydrocarbons in the Blue Amber turn the sun's ultraviolet light into blue light particles. The result: the famous blue glow of Blue Amber. This effect is only possible with Dominican Blue Amber pieces graded within the Blue Amber category. Any other Amber (like Baltic and others) will not display this blue phenomenon at all. And, on top of that other Dominican Amber will show this blue efraction only in concentrated UV light, and not in natural light. Light passed through the Blue Amber from a flashlight, will also result in the normal looking cognac amber color.

Example of same piece of Blue Amber with front lighting, then looking as same piece lighted from the reverse

Thanks to The Amber Ranch for the pieces of and the info on Dominican Blue Amber

"Keokuk Geodes" !

Keokuk Geodes have long been objects of curiosity, their sparkling interiors containing some of the most beautiful crystals to be found anywhere in the Midwest. Although Geodes are known from many localities around the world, one of the most productive and famous collecting regions is encompassed within a 35-mile radius of Keokuk, Iowa. Rock collectors commonly refer to geodes from this region as "Keokuk Geodes." In keeping with the world-renowned status of the Iowa Geodes, the Iowa General Assembly declared the Geodes as the official "State Rock" in 1967.

Geodes from the Keokuk area contain a variety of minerals, but Quartz is dominant in most. Quartz is silicon dioxide, the primary mineral in ordinary sand. Beautiful transparent to white Quartz crystals cover the walls of many Geode cavities. These crystals become larger and fewer in number towards the center of the Geode, and terminate in characteristic pointed hexagonal pyramid shapes. Micro-crystalline Quartz, or Chalcedony, whose component crystals are too small to be seen with the naked eye, forms the outer shell in all "Keokuk Geodes." Chalcedony layers also encrust the interior walls of many Geode cavities, covering the surfaces of the earlier-generation Quartz crystals in a variety of colors, including white, gray, blue, yellow and orange. Calcite is a common and attractive calcium carbonate mineral in many Geodes, which occurs in a variety of crystal habits and colors. An additional 17 minerals have been identified in "Keokuk Geodes.

Iowa's renowned "Keokuk Geodes" can be found in specific stream drainages and excavations in parts of southeastern Iowa, especially in Lee, Henry, and Van Buren Counties, including the area near Geode State Park. Most Geodes are derived from strata of the lower Warsaw Formation, a widespread rock unit of Mississippian age. Muds deposited in a shallow sea about 340 million years ago were primarily calcium carbonate and clay, and were subsequently lithified to form the shales, shaley dolomites, and limestones that we see today. Collecting Geodes can be both fun and educational. Once you've located exposures of lower Warsaw strata or a Geode-bearing stream course, all that's required is a little patience and a good bricklayer's or rock hammer. A sharp blow with a hammer is usually sufficient to crack open individual Geodes, exposing their crystalline interiors to daylight for the first time. However as a Warning, remember that most Geode-collecting localities are now on private land, and written permission must be secured before entering and collecting the Geodes.

Lapidary and Gemstones - unusual finds !

MAW Sit Sit --- A beautiful green colored stone that looks like fine quality jade, which makes sense since one of the constituents that make up Maw Sit Sit is jadeite. It is a metamorphic rock that was formed when higher pressure changed a formation of igneous rocks. The formation had a lot of chromium based minerals such as chromite and chrome rich jadeite, which accounts for the color. Maw Sit Sit has been pretty rare on the market, but more and more of it is appearing as time goes by.

This is a wonderful example of what the gemstone world can offer with an unusual name from a small place that no one has heard of ... until they named a gemstone after it, from a place called Maw Sit Sit in upper Myanmar. Maw sit sit was first identified by the late Dr. Eduard Gubelin in 1963 and named after the village close to the site where it was found. It is currently on the list for non-importation into the USA along with Myanmar (Burma) Rubies unless one can show a purchase date before the law went into effect.

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Zoisite Conglomeriate --- This beautiful combination of Ruby embedded in a matrix of green and black Zoisite is also known as Anyolite. This stone has wonderful red Ruby crystal structure embedded in a natural matrix of green and black Zoisite. It is strikingly dramatic, beautiful and hard to come by. Bright and bold opposite colors contrast to form exquisite patterns people love to look at. Although Anyolite is many times advertised as a variety of Zoisite from Kenya and Tanzania, Anyolite is actually a metamorphic rock composed of intergrown green Zoisite crystals, black Tschermakite cystals, and Ruby crystals. It is said to be named after the Maasai word 'anyoli', meaning "green." The contrasting colours make Anyolite a popular material for sculptures and other decorative objects. It was first discovered at the Mundarara Mine, near Longido, Tanzania in 1954. Much of the material now being called Zoisite Conglomeriate nows comes out of South Africa. Anyolite is also referred to as Ruby in Zoisite or Tanganyika Artstone when smaller amounts of the black Tschermakite crystals are present. Do NOT confuse Ruby if Zoisite with Fushite, especially when it is Ruby in Fushite).

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Septarian Concretion --- Concretions are masses of mineral matter formed when minerals in water are deposited about a nucleus (such as a leaf or shell or other particle) forming a rounded mass whose composition or cement is usually different from the surrounding rock. This can occur at the time of deposition, shortly thereafter, or after the sediment has hardened. Generally, concretions are harder than the rocks around them; therefore, over time the concretions can weather out of the surrounding rocks. Concretions are found world wide, but some of the best come from Wyoming and Kansas. These are formed from any of a number of minerals, including calcite, limonite, barite, pyrite, or silica. They vary widely in shape and size. The smallest are oolites, which can be smaller than the head of a pin. At the other end of the spectrum are the huge spherical Septarian Concretions, the largest of which have diameters of 20 feet or more. The exteriors of septarian concretions are crisscrossed by a network of ridges, giving some of them the appearance of a turtle shell. Geologists think they were formed by the shrinkage of concretions, which caused cracks to form, followed by the deposition of the various such minerals. When the concretions are exposed to weathering, the softer parts between the mineral-filled cracks are eroded and the cracks extend above the surface of the concretion, like ridges or little walls. When cut and polished, they make interesting stones for jewelry, as long as they are well protected. .

Polyhedral Agate - An Unusual Form of Agate !

A very unusual form of Agate comes from Minas Gerais, Brazil. It is known as a Polyhedral Agate and is formed by silica replacing the normal calcite resulting in a highly angular form within the rocks instead of the usual sub-spherical forms as normally seen.
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These polyhedral quartz pseudomorphs without calcite were mined during the 1970’s and have since then become increasingly uncommon in today's market, with most examples appearing as thin slabs, normally polished front and back to show off the natural beauty of the agate. It's sharp polyhedral form is entirely natural in origin.

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Many of the beautiful Agates coming from Minas Gerais today, like the one seen here, will have some slightly pointed sections to their designs, indicating that there is still some silica within the calcite in the Agate itself.

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Collectors scramble to obtain samples of a Polyhedral Agate, especially one that still is made up of most of the host rock as seen at the left in this collection piece from Australia.
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ORTHOCERAS - unique Fossil Jewelry !

Orthoceras was an ancient mollusk that lived more than 400 million years ago. The name means straight horn, referring to the characteristic long, straight, conical shell. Orthoceras is a genus of extinct nautiloid cephalopod. This genus is sometimes called Orthoceratites. Note that it is many times misspelled as Orthocera, Orthocerus or Orthoceros. Orthoceras fossils are common and have a global distribution, occurring in any marine rock, especially limestones. These are slender, elongate shells with the middle of the body chamber transversely constricted, and a subcentral orthochoanitic siphuncle. The surface is ornamented by a network of fine lirae.

Originally Orthoceras referred to all nautiloids with a straight-shell , called an ("orthocone") . But later research on their internal structures, such siphuncle, cameral deposits and others, showing that there are actually a number of groups, even different orders, that they can belong to. The following are a couple of examples.

Many samples of Orthocaras are extremely large and are finished as desk or large display pieces as seen in the following picture.

However, smaller sized pieces make up into very interesting pendants, and sometime earrings.

A wire-wrapped Orthocaras in a pendant design by our daughter-in-law.

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TEKTITES - from out of this world ?

Tektites (from Greek tektos, molten) are natural glass rocks up to a few centimeters in size, which most scientists argue were formed by the impact of large meteorites on the Earth's surface. Tektites are typically black or olive-green, and their shape varies from rounded to irregular. Tektites are still poorly understood. They are irregularly- and at times intricately-shaped nodules and blobs of a glassy substance. They have no crystal structure, and are therefore similar to Obsidian, but are not associated with volcanic processes.

This impact theory of Tektites relies on the observation that Tektites cannot be found in most places on the Earth's surface. They are only found in four strewnfields, three of which are associated with known impact craters. Only the largest and geologically youngest Tektite deposit in Southeast Asia, has not been definitively linked to an impact site, probably because even very large impact structures are often not easy to detect. Also, the bigger the strewnfield, the bigger the area to search for the crater. Since several new craters are identified every year, this is not really regarded as a problem by proponents of the Tektite impact theory.
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The age of Moldavites, also miss-spelled Maldavite, a type of Tektite found in the Czech Republic, has been determined to be 14 million years. This age also exist for Tektites from the North American strewnfield and the Chesapeake Bay impact crater and Tektites from the Ivory Coast strewnfield and the Lake Bosumtwi-Crater.

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Tektites are among the "driest" rocks, with an average water content of 0.005%. This is very unusual, as most if not all of the craters where Tektites may have formed were underwater before impact. Also, partially melted Zircons have been discovered inside a handful of tektites. This, along with the water content, suggests that the tektites were formed under phenomenal temperature and pressure not normally found on the surface of the Earth.

The various known Tektites are:

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European strewnfield:
--Moldavites (Czech Republic, green)

Only Tektites from this area are clear or large enough to be faceted.
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Australasian strewnfield:
--Australites (Australia, dark, mostly black)

--Indochinites (South East Asia, dark, mostly black)

--Chinites (China, black)

North American strewnfield:
--Bediasites (USA, Texas, reddish-black)

--Georgiaites (USA, Georgia, brownish-green)

Ivory Coast strewnfield:

--Ivorites (Ivory Coast, black)

Though the meteorite impact theory of Tektite formation is widely accepted, minority theories propose alternate ideas of Tektite formation.

Also do not confuse Tektites with Meteorities, which will be discussed in a later Blog.

Pictures of Tektites from those owned or from friends collections.

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GEMSTONES - Texas Favorites !

West Texas is famous for its wide variety of unique and beautiful Agates and Jaspers. Some types are highly prized by collectors all around the world. 35 million years ago, volcanic activity in the Big Bend area produced the environment for these beautiful gemstones. Quartz crystallizing as nodules inside gas pockets, or in cracks to form vein type agate, delicate plumes, bands, moss or bouquet patterns of different colors are actually crystals of impurities such as iron oxide, other oxides, hematite, etc. Agates and Calcedony are widespread throughout this region, but only a small amount it is of lapidary interest. Agate has been found south of Sierra Blanca, all the way down the Rio Grande, past Del Rio. Texas has no public lands to collect on, so there is still a lot to explore, if permission can be obtained from the ranchers. Just remember, don't go past a fence line without a ranchers permission, you might regret it !

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One of the most famous is Red Plume Agate made famous by the Woodward Ranch. The ranch, located south of Alpine, offers Agate collecting for a fee. There are also trips out of Alpine to the Walker ranch for a daily fee. Although Red Plume is found only on the Woodward Ranch, there are several other types of Agates to be found on the Woodward Ranch, as well on other ranches in the Alpine and Marfa areas. Black and Brown Plume Agate are the most common lapidary grade. Banded Agate is also fairly common and near Alpine it is usually white, nearly clear, but can be shades of red, purple or pink, often surrounding a plume. Yellow Plume Agate can be found in the area but is difficult to cut. There is a type of Orbicular Agate found south of Alpine called Peanut Agate which can be quite beautiful. Most of the lapidary grade Agate found south of Alpine is found in biscuit shaped nodules with a dark red skin.

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Marfa Texas has some of the most beautiful Bouquet Agate in the world that come in pastel colors in "bouquet" patterns and are the most sought after by collectors. The bouquet pattern can be found with black plume in both white skin and black skin Agate. A lot of this Agate is egg shell, thin coating of Agate lining the gas pocket, often with the botryoidal crystals. This usually is a good sign of quality plumes or bouquet. Black skin egg shell typically is black or blue and white banding. Balmorael Agate is famous for its blue color, banded often with black plumes. The skin is usually black with a white patina on the surface. It appears to be fairly wide spread in isolated pockets northwest of the Davis Mountains.

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Topaz, the state gem of Texas, is found within the borders of the state only in Mason County. It occurs in granite outcroppings principally in the Streeter, Grit, and Katemcy areas. It is usually found in streambeds and ravines but occasionally can be located atop the ground. Topaz resembles quartz and ranges in color from clear to brown to yellow to sky blue. The blue stones are especially beautiful and extremely rare, and most interesting when faceted in the Lone Star cut.

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Llanite is a hypabyssally intruded Rhyolite with phenocrysts of microcline and euhedral Quartz. The quartz crystals are blue hexagonal bipyramids. The unusual blue coloration of the Quartz is thought to be due to ilmenite inclusions. This gemstone is named after Llano County, the only place in the world where Llanite is found. A dike of Llanite outcrops in the Texas Hill Country north of the town of Llano. Rough, especially older material will have a definite reddish cast, but newer finds and finished and polished stones tend more towards the gray tones, but the blue Quartz stands out no matter when dug. Then in the Marble Falls and Burnett areas one can find all kinds of Granite and Marble. These are primarily used for counter tops and building construction.

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We have just barely scratched the surface of the various unique as well as common gemstones and rocks that can be found within the State of Texas. Several books are available and many sites can be Googled on the Internet to obtain the names of the ranches that allow rock collecting as well as groups and persons who will act as guides. In winter, be prepared for a cold and wet trek, in summer a scortching hot, dusty and windy trek. Just remember, many great finds have been made along the highways cuts and grades as one drives this very large and diverse State. Here is a short list of what can be found in Texas:::

[number in ( ) is identified specific varieties]

AGATE (some 17+)

AMETHYST

AMMONITES

ANDRADITE

ARTHROPODS

BASALT

BRACHIPODS

CALCITE

CELESTITE

CEPHALOPODS

CHALCEDONY (some 9+)

CINNABAR

DOLOMITE

FELDSPAR (some 4+)

FLINT

GALENA

GARNETS (some 6+)

GASTROPODS

GEODES (unknown number)

GOETHITE

GRANITE (some 26+)

HEMATITE

JASPERS (some 21+)

LIMESTONE

LLANITE

MANGANITE

MARBLE (some 14+)

MICA

MOONSTONE

OLIVENE

OPAL

PALM WOOD

PEGMATITE

PERIDOT

PETRIFIED PALM

PETRIFIED WOOD

PYRITE

QUARTZ (some 8+)

RHYOLITE (some 3+)

SAGENITE

SELENITE

SERPENTINE

SPHALERITE

TEKTITES

TOPAZ (some 7+)

TRILOBITES

WONDERSTONE

WULFENITE

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BLACK ONYX - a manmade variety of Chalcedony (Agate) !

Every now and then, a real surprise comes along and makes one step back and wonder about many other things. One such rendering took place this past weekend at the Southwest Gems and Mineral Society Show. Was told by a knowledgable lapidarist when looking at a display I had, than there isn't such a thing as "Black Onyx" which was included in several of the necklace sets I had on display. So started checking around, and the Earth Science Department from Trinity University was present with a booth, so chatted with them for a bit, and yep, no such thing as natural "Black Onyx". To make things easier to understand, here are some definitions of "Black Onyx" off of several different sites on the Internet.

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"Black onyx" is neither truly onyx nor truly black, but it is actually dyed chalcedony. According to some experts, it is produced by boiling slabs of gray chalcedony in a sugar solution. The sugar permeates the stone's "pores" between the submicrocrystallites and darkens the appearance of the stone. This dye/treatment is stable and requires no special care.

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Black Onyx - unknown in nature, it is produced by warming chalcedony in a sugar solution for several days or weeks. The stone in then placed in warm sulphuric acid. The acid reacts with the sugar, precipitating the free carbon. The black color is permanent.

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Black Onyx - Mohs Hardness: 6.5-7 - Treatment: Dyed for color uniformity - Color: clear to browns (See also Chalcedony as no such thing as Black Onyx). Onyx and Sardonyx are similar to agate, but Onyx has straight rather than curved bands. These bands may be in shades of browns, reds, tans, yellow, greens and rarely blues and will always have white. Since ancient Egyptian times, onyx has been stained to improve or change its color to an all black gemstone. All totally black onyx has been produced by soaking black agate (chalcedony)or other Onyx, especially clear, in a sugar solution, then heating it in sulfuric acid to carbonize the sugar particles. Found worldwide. Onyx is formed by the deposition of silica in gas cavities in lava, which results in the distinctive bands.

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So from now on the proper term to use with the 'little or big black stones' used in jewelry, should be either black Agate or black Chalcedony with the added comment "enhnaced by chemical treatments and is called black Onyx". One learns something new every day if you listen good.

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QUARTZSITE - A major prelude to Tucson 2010 !

Welcome to QUARTZSITE and Desert Gardens on the California - Arizona State Line.

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2010 Calendar of Events

January 01 - February 28, 2010 Desert Gardens-Gem & Mineral Show

January 01 - January 10, 2010 Tyson Wells Rock & Gem Show

January 09 - February 24, 2010 Main Event

January 15 - January 24, 2010 Tyson Wells Sell-A-Rama

January 16 - January 24, 2010 Sports, Vacation & RV Show

January 27 - January 31. 2010 Hobby Craft & Gem Show

January 29 - February 7, 2010 Tyson Wells Arts & Craft Fair

January 20 - January 24, 2010 Annual Pow Wow

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Then it is on to the Tucson Gem Fair 2010 during February !

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When its clear it is beautiful, but then the wind and sand rolls in.
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but the Show goes on, and the weather clears again.

There is plenty to see, masses of rock and minerals all over the place, inside and out.

Tables of new material, like Imperial Sarah Jasper,

or buckets of everything and anything imaginable,

and hugh slabs of Tigereye and TigerIron,

or maybe even some unknown wierd stuff.

How about a Geode big enough to stand or sit in
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and a few odd things also.

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Whatever you want, you could probably find it at QUARTZSITE and for sure at the following Tucson Gem Fair 2010. Many of the vendors at QUARTZSITE will move to Tucson as the various different shows open up there during the month of February.

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Pictures thanks to Ron, theimage1 and Quartzite.com.

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