Garnet w/Quartz (I)
Garnet w/Quartz (I)

Garnet w/Quartz (I)

Regular price $600.00
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GARNET VAR. SPESSARTINE
WITH SMOKY QUARTZ

Wushan Spessartine Mine
Tongbei, Yunxiao Co.
Fujian Province, China

Cabinet
2.5 x 1.5 x 2.3 Inches
6.5 x 4 x 6 Centimeters

Two classic minerals come together to form a very aesthetic specimen from this famous Chinese mine. Small to large gemmy orange garnets cover the matrix and cling to the smoky quartz - Several garnets have grown inside of the large smoky point - This is a great specimen to hold and examine closely, it also sits nicely for display. Specimens from the Wushan Spessartine Mine are considered Chinese classics as the mine is now closed.

Garnet is the name used for a large group of rock-forming minerals. These minerals share a common crystal structure and a generalized chemical composition of X3Y2(SiO4)3.

These minerals are found throughout the world in metamorphic, igneous, and sedimentary rocks. Most garnet found near Earth's surface forms when a sedimentary rock with a high aluminum content, such as shale, is subjected to heat and pressure intense enough to produce schist or gneiss. Garnet is also found in the rocks of contact metamorphism, subsurface magma chambers, lava flows, deep-source volcanic eruptions, and the soils and sediments formed when garnet-bearing rocks are weathered and eroded.

The most commonly encountered minerals in the garnet group include almandine, pyrope, spessartine, andradite, grossular, and uvarovite. They all have a vitreous luster, a transparent-to-translucent diaphaneity, a brittle tenacity, and a lack of cleavage. They can be found as individual crystals, stream-worn pebbles, granular aggregates, and massive occurrences.

Calcium garnets typically form when argillaceous limestone is altered into marble by contact metamorphism along the edges of igneous intrusions. These are andradite, grossular, and uvarovite, the slightly softer, typically green garnets with a lower specific gravity. Two calcium garnets are highly regarded in the gem trade; they are tsavorite (a bright green grossular) and demantoid (a golden-green andradite).

Spessartine is an orange garnet found as crystals in granite pegmatites.

Credit: Geology.com

Quartz has been known and appreciated since pre-historic times. The most ancient name known is recorded by Theophrastus in about 300-325 BCE, κρύσταλλος or kristallos. The varietal names, rock crystal and bergcrystal, preserve the ancient usage. Quartz is one of the most common minerals found in the Earth's crust.

If pure, quartz forms colorless, transparent and very hard crystals with a glass-like luster. A significant component of many igneous, metamorphic and sedimentary rocks, this natural form of silicon dioxide is found in an impressive range of varieties and colours.

Quartz is found as individual crystals and as crystal aggregates. Well crystallized quartz crystals are typically six-sided prisms with steep pyramidal terminations. They can be stubby ("short prismatic") or elongated and even needle-like. In most environments quartz crystals are attached to the host rock and only have one tip, but double-terminated crystals are also found.

Quartz is best known for the beautiful crystals it forms in all sorts of cavities and fissures. The greatest variety of shapes and colors of quartz crystals comes from hydrothermal ore veins and deposits, reflecting large differences in growth conditions in these environments (chemistry, temperature, pressure). Splendid, large crystals grow from ascending hot brines in large fissures, from residual silica-rich fluids in cavities in pegmatites and from locally mobilized silica in Alpine-type fissures. An economically important source of amethyst for the lapidary industry are cavities of volcanic rocks. Small, but well-formed quartz crystals are found in septarian nodules, and in dissolution pockets in limestones.

Credit: Mindat.org


VARIETIES:

Amethyst: Typically a purple variety due to iron impurities and irradiation - Iron is captured during crystallization and surrounding materials release gamma rays irradiating the iron. Occurs worldwide with documented uses from Ancient Greek and Egyptian cultures.

Cactus Quartz: Large amethyst and/or citrine quartz crystals covered with smaller spiky crystals - Only found in Boekenhouthoek, South Africa

Vera Cruz: Elongated and prismatic crystals only found in Vera Cruz, Mexico

“Grape Agate”: A popular but misleading name - the “agate” is actually botryoidal amethyst quartz.

Smoky Quartz: Smoky brown and grey hues created by irradiation of trace aluminum captured during crystallization. Varies from translucent to opaque depending on amount of surrounding radioactive emissions. Occurs around the world with popular localities including Colorado, Scotland, Africa and Switzerland.

Herkimer Diamond: Local name for clear, doubly-terminated, usually quite clear and highly lustrous, quartz crystals from cavities in dolostones in Herkimer Co., New York, and surrounding areas, USA. They are frequently doubly terminated with prism faces about as prominent as the pyramidal terminations. They were originally (1790) named "Little Falls Diamond(s)". There are similar terms for quartz crystals from numerous other worldwide locales, all formed under low-temperature hydrothermal conditions in sedimentary rocks and often containing hydrocarbon inclusions.

Herkimer diamonds have been popular with collectors for more than 100 years and various localities for them in Herkimer Co. are still producing many specimens each year even though it requires a lot of hard manual labor to find good specimens. Credit Mindat.org

Faden: Forms in fissures in the host rock that widen slowly and steadily. Quartz crystals inside the host rock will rupture when the fissure opens. In a silica rich solution, this rupture will heal quickly, forming a crystal that is attached to the opposing rock walls and bridges the new opening. While the fissure continues to open steadily, the crystal will also continue to crack and heal. Because growth is much quicker on fractured surfaces than on regular faces and because it leads to small regular faces on the opposite conchoidal fracture surfaces that do not perfectly match, some of the growth solution is included in the crystal. The repeated rupturing and healing leaves a scar of liquid and gas inclusions in the crystal: a white thread, the "faden". Credit Mindat.org

Prase: Originally, the varietal name "prase" was applied to a dull leek-green colored quartzite (a rock, not a mineral*); but over the years it has also been applied to other materials, particularly a green colored jasper of similar color. For perhaps more than a century it was restricted to granular micro-crystalline varieties of quartz and the original quartzite; but in recent years euhedral crystals of quartz having a similar leek-green color have had the term applied to them as well, expanding the definition beyond micro-crystalline forms. Now it is simply a color descriptor for quartz: If it is leek-green, it is called "prase" - whether it is micro- or macro-crystalline, and no matter what causes the color. Basically, the term no longer has any scientific rigor - it has become a general term; it can't even truly be called a varietal name any longer - since it covers more than one material. Credit Mindat.org

MINERALS:
We guarantee the mineral specimen you purchase will be the exact item you receive. It is important to us that you enjoy your mineral specimen as much as we enjoyed sourcing it for you. We use professional photography and video to show you every inch of the specimen using optimal lighting/setup conditions. If you want to view a specimen from a certain angle or lighting source we are happy to provide more images/videos at your request.

Minerals over $1,000 include a certificate of authenticity from Invenio Fine Minerals. We only issue a certificate of authenticity for minerals we sell.

Measurement Descriptions:
Thumbnail: 0.2 to 3 Centimeters / .0625 - 1.118 Inches
Miniature: 3+ to 5 Centimeters / 1.125 - 1.96 Inches
Cabinet: 5+ to 9.5 Centimeters / 2.0 - 3.7 Inches
Large Cabinet: Greater than 10 Centimeters / Greater than 4 Inches

Minerals pictured attached to an acrylic base will be delivered attached to the base. We can unmount the specimen for you if you prefer.
We offer basic and custom mineral mounting services, contact us for more info.

PURCHASING:
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SHIPPING:
We use premium packaging materials to protect mineral specimens, every order is carefully packaged and thoughtfully protected. 

Shipping in the United States:
Free shipping in the United States!

Tracking is included on every purchase
Insurance is optional, please read below


Worldwide Shipping:
$55 flat for all international orders* 
*Certain restrictions and additional charges may apply depending on buyers location*

We only ship orders to the UK and EU with a value over $200 USD

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Buyer is responsible for all import taxes and fees.

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US Shipping Insurance:
Insurance is not included on all orders. We insure packages on a case-by-case basis, if you would like to insure your package please contact us.

Damage or Loss:
If your mineral is damaged or lost during shipment we will work with you to compensate you for the issue. Shipping times are currently longer than usual because of COVID so please be patient if your tracking is not updating regularly.

If your package arrives damaged please keep ALL of the original packaging as it may be required by the shipping service for an insurance review. Contact us immediately with any issues.

Please unpack your mineral/s with care, we are not responsible for damage during unpacking.

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