Emeralds, color

Colored Impregnations. Colored oil to fill cracks is used on gemstones primarily to improve color, most frequendy on emerald. Colored oil is also used to simulate other stones, most frequendy quartz. Depending on the dye used, the colors may fade, in addition to the problems associated with colodess oiling. 

Other copper compounds are found in battery fluid fabric dye fire retardants food additives for farm animals fireworks (bright emerald color) manufacture of ceramics and enamels photographic film pigments (coloring agents) in paints, metal preservatives, and marine paints water purification and wood preservatives. 

This salt give a very beautiful emerald color but its high coA, viz sbout 30c Ib. makes it little used except in exhibition work. Some recipiea have been given for green fire using boracic acid, thalium aalta etc. but if uaed at all it is to a very limited awtent All barium aalts are very poisonous. 

Chromium is used to harden steel, to manufacture stainless steel, and to form many useful alloys. Much is used in plating to produce a hard, beautiful surface and to prevent corrosion. Chromium gives glass an emerald green color and is widely used as a catalyst. 

Beryl. Beryl [1302-52-9] Be Al Si O g, is called aquamarine [1327-51 -1] when pale green or blue from inclusion of Fe emerald [12415-33-7] when dark green from Cr or at times V, and morganite or red beryl when pink or red, respectively, from Mn. Only the synthetic emerald is in commercial production, although the other colors can also be grown. Both the flux and hydrothermal techniques are used to grow this luxury synthetic. 

A thin layer of dark green beryl had been grown by a hydrothermal technique over the surface of a pale beryl to imitate emerald. It has been suggested that such stones should be called synthetic emerald-beryl doublets (16). The abiHty to grow thin, but not thick, single-crystal diamond on the surface of natural diamond (17) leads to the possibiHty of growing such a thin film colored blue with boron this has been done experimentally (18). 

FIGURE 14.20 An emerald is a crystal of beryl with some Cr + ions, which are responsible for the green color. 

This workbook is a guided tour through the steps of the Emerald Formula. There are alchemical mandalas and symbolic drawings actually used by the alchemists to illustrate the principles of the Emerald Tablet, as well as interpretations and guided meditations to accompany them. Most engravings have never before been published to a wide audience and date back over five hundred years others have been restored with symbolic colors to convey their archetypal content. [By D.W. Hauck ]... 

A colorless mineral known as corundum (composed of aluminum oxide) is colorless. A red variety of corundum known as ruby, a precious stone, owes its color to impurities of chromium within the crystal structure of corundum. Blue and violet varieties of corundum are classified as sapphires, the blue being the result of iron and titanium impurities, and the violet of vanadium impurities within the corundum crystal structure. Another colorless mineral is beryl (composed of beryllium aluminum silicate) but blue aquamarine, green emerald, and pink morganite, are precious varieties of beryl including different impurities aquamarine includes iron, emerald chromium and vanadium, and morganite manganese. 

Mineral gemstones that have the same basic chemical composition, that is, are composed of the same major elements and differ only in color, are considered as variations of the same mineral species. As gemstones, however, minerals that have the same composition and crystalline structure but exhibit different colors are classified as different gemstones. Beryl, for example, a mineral (composed of beryllium aluminum silicate), includes a pink variety, known by the gemstone name of morganite, and also a well-known green variety, emerald. Table 18 lists and classifies, by composition and color, gemstones that have been appreciated since antiquity. 

A bright emerald green color (usually) develops as the addition proceeds. If the iodine is impure, a brown color develops with no decrease in yield. 

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