Johndocs

Mineral️️A natural, inorganic substance with a characteristic chemical composition and usually characteristic structure. Mixed cut️️A cutting style that combines brilliant-cut and step cut facets. Abrasions️️Tiny nicks and pits caused by wear and damage to a gem's facet edges or culet. Absorption spectrum️️A pattern of dark vertical lines or bands shown by certain gems when viewed through a spectroscope. Adularescence️️The cloudy bluish white light in a moonstone, caus...

commercially important gems️️Treatments that improve gem appearance and quality increase the supply of... available, affordable️️Treatments that make gems more _____________ and ____________ are an important part of today's gem and jewelry market. disclosed️️All treatments, even suspected or probable treatments, should be ______________ as part of every transaction. gems that are commonly heat treated️️Corundum, tanzanite, zircon, topaz, aquamarine, and amber. heat treat...

species or variety️️You should judge a gemstone's beauty and value only by comparing it with others of its own ___________ or ___________. large stones️️_____________ ____________with fine color are more common in some colored stone species than in others. pure hues️️In many gemstone varieties, _________ _____ are more valued than mixed hues. shouldn't️️You __________________ use trade terms that imply a gem's geographic origin if you can't be sure of its actual source....

silica spheres️️Precious opal is made of billions of uniform submicroscopic _________ ___________, stacked in an orderly pattern. light️️Play-of-color is produced by the interaction of _________ with opals internal structure of stacked silica spheres. black opal️️_________ _________ commands the highest prices of all opal types. white opal️️_________ ________ makes of the bulk of commercial-quality opal on the market. matrix backing️️____________ ____________ often mak...

The most desirable emerald colors are _________ green to green, with strong to _________ saturation and __________ to medium-dark h, vivid, medium️️bluish, vivid, medium The trade considers emerald to have the finest _________ among colored stones.️️green Slight differences in hue, tone, and saturation can make a great difference in emerald __________ when other factors are equal.️️value emerald's color-causing trace elements are️️Chromium, vanadium, and iron Poor ________...

color️️This is the most important factor in determining a colored gemstone's desirability, marketability, and value. light️️This is a form of energy that travels in waves. selective absorption️️Most gem color is caused by... chemical composition and crystal structure️️Selective absorption is influenced by... (2) visible light️️Some colored gems can be identified by the way they absorb... trasition element️️Because of differences in crystal structure, the same ____...

sapphire️️The word "___________," when used aloe typically refers to the blue variety of corundum. popular️️Blue sapphire is one of the most ____________ colored stones, especially in the US. velvety, violetish, medium, medium, dark, strong, vivid️️The most highly valued blue sapphires are ___________ blue to _____________ blue, in __________ to ___________- __________ tones, with __________ to _________ saturation. iron, titanium️️The trace elements ______ and __________...

per-carat️️Ruby can command the highest ______-__________ price of all colored stones. 9️️Ruby rates ____ on the Mohs hardness scale, so it's ideal for frequently worn jewelry. purplish, dark, vivid️️The most valuable ruby colors are red to slightly ____________ red with medium to medium-_______ tones and __________ saturation. division️️Not everyone agrees on the _______________ between ruby and pink, purple, or orange sapphire. chromium, fluorescence️️The trace eleme...

large gems️️___________ ________ are ore rare than small ones, so they often cost much more per carat, even if they're of equivalent quality. weight️️Most colored stones are sold by _____________. carat weight, dimensions️️A gem's recorded ________ ________ and _____________ can help identify it later. Leveridge️️A _________________ gauge is one of a stone dealer's most useful and versatile tools. 0.10️️The sizes of calibrated gems in a parcel should be within _____...

transparency, brilliance, durability️️Clarity characteristics that affect these three things have the most influence on value. less noticeable️️Cutters often leave cavities in _______ __________ areas to avoid weight loss from expensive rough. nature, size, number, position, relief️️Five factors that determine the influence of clarity characteristics on marketability (NSNPR). clarity standards️️Some types of colored stones are typically more included than others, so they'...