Parting in Gems
The term "parting" refers to a phenomenon that is similar to cleavage in that it is a "plan of weakness" that can easily cause the stone to fracture with a small amount of force.
Parting
Flat, smooth breakage of a mineral along planes or twinning, commonly found in corundum.
Paste
Glass usually containing lead oxide and cut to simulate a gemstone.
Parting results from "lamellar twinning," a process in which two crystals grow together in the same plane.
Parting...A smooth fracture that looks like a cleavage plane but takes place only on certain planes in the crystal, not between any set of atoms, like true cleavage.
Paste...Lead glass imitation stone.
parting The tendency of certain minerals to split along stressed areas or along twinned crystals. passive continental margin A border that lies between continental and oceanic lithosphere, but is not a plate margin.
For thousands of years opals have been regarded as a source of imparting inner beauty and faithfulness to the wearer.
At that very moment he was departing for a few days' stay at the meershaum locality. Upon telling him of my interest in ruby corundum, he thereupon drove me directly to his home.
Parting - The ability of a mineral to separate along definite directions, along twinning or gliding planes.
Pearly - A luster description showing a glimmering sheen as in the surface of a pearl.
If you plan to buy some stone jewllery, it is mandatory that before parting with your cash know about the basic traits of the gemstone in question. Onyx, which is microcrystalline quartz, belongs to chalcedony family.
Cleavage, fracture, and parting. Because bonding is not of equal strength in all directions in most crystals, ...
Some of the indestructible pearls are made over beads of opalescent glass, thus imparting a finer effect to the finished product.
Ruby has no cleavage but has preferred directions of parting. Inclusions are common and not an indication of lower quality.
Some stones will have the three Cs (color, clarity, and cut), but very few also have the diaphaneity, the good crystal - the fourth C, imparting a quality that is rich, crisp, and velvety all at the same moment.
It is defined as any break that other than that caused by cleaving or parting. Fractures may be internal or external. Internal fractures are called feathers.
{110} good, 100 moderate, parting on {092} and {011}
Fracture
Uneven to sub-conchoidal ...
Niello is a black alloy of Silver, Copper, Lead and Sulphur. It is used to fill engraving, imparting an inlaid effect after the metal is fired and polished.
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z ...
SMELTER ASSAY - Analysis of Gold and Silver in "low-grade" Smelter feed material by Lead Collection followed by Cupellation and Parting; also used in conjunction with spectroscopy to determine Platinum, Palladium and Rhodium.
Today, Stainless Steel jewelry is a favorite of both men and women that want an industrial, street look with a touch of flash. Departing from tradition, Stainless Steel jewelry can be found in the use of machined pendants, ...
Winter 1964, Partings in black star sapphires, p. 250, 1p.
Winter 1968, An inclusion in alexandrite-like sapphire from Montana, p. 373, 1p.
Summer 1969, X-ray bombarded yellow sapphires, p. 57, 1p.
Summer 1969, A 277 ct.
The process of artificially changing or enhancing the colour gemstones, especially a porous stone (e.g. agate), by causing a colouring chemical (or carbon) to enter the pores of the stone, or of imparting a colour to certain colourless stones, ...
Spondumene is strongly pleochroic and hence a great challenge for gem cutter. A great care is taken to orient the stone in the best position to obtain the deepest color. The cleavage, parting and fracture of the stone is also a tough job for any gem ...
METALLURGY. The art of separating metals from their ores or from impurities; smelting, reducing, refining, amalgamating, alloying, parting, brazing, plating, etc.
For evening wear, the fashion was to have the hair swept up and dressed with diamante' combs, bunches of feathers, perhaps a fresh flower or two and a jewelled harem band across the brow. Daytime styles favoured a side parting on the left and ...
The usual rhombohedral form also occurs, and crystals are frequently terminated by a basal plane. Basal and rhombohedral partings frequently occur, and in consequence of these, basal "cleavage" plates, ...
Burned-on sand and scale are removed to improve the surface appearance of the casting whereas excess metal, in the form of fins, wires, parting line fins and gates, is also removed. Cleaning of metal casting can be done by many ways: ...
It is used to fill engraving, imparting an inlaid effect after the metal is fired and polished.
Nickel silver (also called German silver) is a white metal alloy of 70% copper, 20% zinc and 10% nickel. It contains no silver.
 See also: Stone, Jewel, Diamond, Crystal, Rough
  
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