Search results
Results from the WOW.Com Content Network
A ruby is a pink to blood-red colored gemstone, a variety of the mineral corundum (aluminium oxide). Other varieties of gem-quality corundum are called sapphires. Ruby is one of the traditional cardinal gems, together with amethyst, sapphire, emerald, and diamond. [1] The word ruby comes from ruber, Latin for red.
The Gemological Institute of America (GIA) is a nonprofit institute based in Carlsbad, California. It is dedicated to research and education in the field of gemology and the jewelry arts. [1] Founded in 1931, GIA's mission is to protect buyers and sellers of gemstones by setting and maintaining the standards used to evaluate gemstone quality.
Stone weight with Darius the Great–era tri-lingual inscription. 9,950g The Eschborn Museum's 2nd-century stone weight of 40 Roman pounds (c. 13 kg), beside an ID-1-sized card for scale The name "stone" derives from the historical use of stones for weights, a practice that dates back into antiquity.
The carat fractional system is increasingly being complemented or superseded by the millesimal system, described above for bullion, though jewelry generally tends to still use the carat system. Conversion between percentage of pure gold and karats: 58.33–62.50% = 14 c (acclaimed 58.33%) 75.00–79.16% = 18 c (acclaimed 75.00%)
In 1986, California named benitoite as its state gemstone, a form of the mineral barium titanium silicate that is unique to the Golden State and only found in gem quality in San Benito County. [ 80 ] ^ Colorado is the only state whose geological symbols reflect the national flag's colors: red (rhodochrosite), white (yule marble), and blue ...
Toggle the table of contents. List of gemstones by species. 6 languages. ... This is a list of gemstones, organized by species and types. Minerals
While the difficulty of obtaining macroscopic samples of synthetic elements in part explains their high value, there has been interest in converting base metals to gold (Chrysopoeia) since ancient times, but only deeper understanding of nuclear physics has allowed the actual production of a tiny amount of gold from other elements for research ...
Gem identification is basically a process of elimination. Gemstones of similar color undergo non-destructive optical testing until there is only one possible identity. Any single test is nearly always only indicative. For example: The specific gravity of ruby is 4.00, glass is 3.15–4.20, and cubic zirconia is 5.6–5.9 . So one can easily ...