Vintage Turquoise Beads from Hubei mines

Vintage Hubei mine turquoise

We recently acquired a treasure trove of high-quality Hubei Turquoise beads from the 1980’s with beautiful clear light blue-green to medium blue-green color.  These beads belonged to a retired owner of a now-closed small company that manufactured sterling silver and gold filled jewelry using high quality semi precious gemstones and semi-precious gemstone beads.  These beads have not seen the light of day for around 35 years and  are now available on our website.  They are mostly AA grade quality and light to medium blue-green. We suspect that our turquoise was mined in Zushan County due to its uniform color and light blue hue.  Like most of our vintage bead lots, we have a variety of small lots of different shapes and sizes, all in limited quantities.  Read on for our gemstone expert GIA certified Alison Bies article about Chinese turquoise:

Turquoise is broadly used in jewelry and artifacts because of its alluring color. One thing that sets turquoise apart from other gemstones are the distinct characteristics of stones from different mines. Turquoise has a long history and has played a crucial role in numerous cultures worldwide, such as ancient Egypt, Iran, China, Mexico, and the Americas. The gem’s name comes from the French expression pierre tourques, or “Turkish stone.” The name, which originated in the thirteenth century, reflects the fact that the material probably first arrived in Europe from Turkish sources, although actual origin may have been elsewhere.  Turquoise was used earlier in Eurasia. In 1977, more than 1,000 turquoise relics in the form of carved cicadas, frogs, and other animals were unearthed from ruins dating to the Yin Dynasty (about 1300B.C.) in Anyang, Henan. Gem-quality Chinese turquoise is relatively pure and tough, with a fine and smooth appearance like jade, simple and elegant in color, and shines like porcelain when polished.

Turquoise is closely interwoven with Chinese civilization through their art and fashion. The Chinese used it for decoration as early as the beginning in the Neolithic age. The earliest turquoise artifacts in China were discovered at the Jiahu site in Wuyang County, Henan Province, (7000 – 5800 BCE). Throughout the long development of Chinese culture and history, turquoise has been abundant with connotations and functions related to decorative, economic, and religious aspects. It has always been regarded as an exclusive and precious gemstone in China, especially in Tibet and Inner Mongolia. Turquoise artifacts recorded the development of human society and reflected exchanges between cultures. Researchers have succeeded in developing methods of origin traceability of turquoise in the southwestern United States and northern Mexico using hydrogen, copper, lead and strontium to identify the source of turquoise artifacts. Similar approaches were applied to investigate the turquoise artifacts from different regions of China.

The preferred stone for most Chinese jewelry and carvings has traditionally been jade. Early evidence of early Chinese turquoise is sparse; however, some areas of China prefer turquoise to jade. The Tibetans use turquoise more than any other gemstone. Believed to contain metaphysical powers, curative qualities and good luck, it is worn in jewelry and adornment directly on hats and other clothing. The Tibetans also use necklaces of felt with turquoise to adorn their domestic animals such as horses.

Turquoise from mines in China accounts for about 80% of the stone on the U.S. market today, due to the scarcity of American turquoise. In China, lesser quality rough turquoise was traditionally treated with wax, resin, or polymers because of its high porosity. However, Chinese consumers prefer natural turquoise rather than artificially treated and synthetic counterparts. Thus, resin and polymer treatments are not as acceptable in the Chinese turquoise trade or as common as in the past. In the 1980’s, the Zachary Method of stabilizing turquoise was developed, which is undetectable using classical gemological methods. Earthly Adornments current offering of turquoise predates the Zachary Method.  Most of our beads are natural turquoise, or identified if they are color enhanced.  Another recent treatment is “porcelain enhancement,” designed to improve the compactness, densification, and luster of turquoise. Its key techniques are still confidential and not publicly available.

Turquoise deposits are widespread in China, including Zhushan County in Hubei Province, the in Anhui Province, and Shanxi Province, Henan Province and in the Xinjiang Uyghur Autonomous Region. The turquoise mined in Yun County, is regarded as top quality. The output from Yun County between 1954 and 1999 totaled more than 800 tons, but its resources are depleting. The deposits in Zhushan County were discovered later, and much is still about their distribution and complex geologic formation is still being discovered. While the material from Zhushan County is often of high quality, with a dense texture and an attractive uniform coloration, mining activity has been intermittent.

Turquoise production from Zhushan County ranges from 50 to 129 tons annually. The Zhushan County turquoise deposits are in a mountainous region of central China. More than 100 mine tunnels have been worked the deepest reaching ~300 m. The turquoise occurs in the Cambrian-age Shuigoukou Formation, within thick- and thin-bedded slates. The mineralized zones generally extend northeast-southwest and follow the regional tectonic structure. The turquoise is found mostly as lenses along faults and as fillings within fractures. The Zhushan County turquoise occurs mainly as veins, blocks, and nodes. It is generally compact, massive, and shows a waxy luster. Its color is predominantly a medium bluish green. Light bluish green, light green, and even yellowish green are also somewhat common, while “azure” blue is rare. The highest quantity and quality of turquoise is typically found where faulting created compressed lenses. The turquoise is often associated with limonite, quartz, kaolinite, and other clay minerals. Turquoise from possessing a compact structure usually does not require treatment.

Numerous detailed characteristics of turquoise from these locations have been reported in recent years, including its spectra, structure, and chemical and mineral compositions. Grape-like structures are sometimes seen, while turquoise with a nodular texture is of the highest quality. It’s surface is characterized by bulbous irregularities called blebs. A bleb is a small bubble-like inclusion of one mineral within a larger mineral. Blebs tend to be brightly colored.

Hubei Province is the largest commercial source in the world. Rich phosphate, iron, and copper ores are the main sources for turquoise formation. Most of the rough turquoise mined from these deposits is surrounded by black rocks that easily distinguish them from those mined in other locations. In 2015, a massive blue rough turquoise, together with its enclosing rocks weighing more than 11 tons, was extracted in Zhushan County, Hubei Province. Miners had to divide it into two parts to transfer them out of the mine. The mines located in Hubei Province have produced many high-quality and unique turquoise with special patterns. It produces turquoise with special patterns, including, “Tang tricolor,” “growth layer,” “spiderweb, “water grass vein,” and “Ulan flower”, “banded”,  “fingerprint” and even “raindrop” patterned. Material with this pattern displays blue and blue-green color spots resembling raindrops, occasionally accompanied by veins. Researchers have made great effort to investigate gem turquoise’s gemological and mineralogical characteristics, color, and concentration of trace elements and rare earth.

The finest turquoise specimens are evenly colored "sky blue" nodules, and rival the finest turquoise from other, more famous localities. In the United States, turquoise is one of the birthstones for December.

 

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