Search Results
Fine Jewelry University Articles matching: “Blue sapphire 10kt”
Showing only FJU Article results. Click here to show all results.
Fine Jewelry University
-
Gem in the Spotlight: Emerald
… and aquamarine) and are valued for their rich green color. The intensity of an emerald’s hue depends on the presence of chromium and vanadium in the crystal structure. Emerald’s Mohs hardness rating is 7.5-8 making it softer than sapphire and harder than amethyst and other quartz varieties. The refractive index of emerald ranges from 1.57 to 1.58, making it a moderately refractive gemstone. Its specific gravity ranges from 2.65 to 2.75. One of the distinctive features of …
-
Gem in the Spotlight: Quartz
… Bloodstone Green jasper dotted with bright red spots Carnelian Reddish orange chalcedony Gemology of Quartz Quartz is known for its durability with a Mohs hardness rating of 7 (harder than opal and peridot but softer than topaz or sapphire). This makes it a fairly hard gemstone that is resistant to scratching and chipping. It is also resistant to heat and chemicals, which means that it can withstand daily wear and tear very well. All quartz has the same refractive index at…
-
Gem in the Spotlight: Pearl
… Pearls: Also known as black pearls, Tahitian pearls are a type of saltwater pearl that are grown primarily in French Polynesia. They are known for their dark, rich colors, which range from dark green and gray to deep shades of blue and black. Tahitian pearls are generally large with an average size of 9mm to 18mm, and they commonly have baroque or irregular shapes. South Sea Pearls: Only a small percentage of oysters are able to produce these large, high-quality pearls…
