Color amethyst

The electron can be trapped, for example by an interstitial which is converted to an H atom. The AlO is the hole color center which absorbs light and gives the color to smoky quart2. Bleaching is the result of thermal energy releasing the trapped electron, which then produces the reverse of reaction 1. The amethyst color center in quart2 is exactly like the smoky, except that Fe " replaces. ... 

There are four allotropic forms of manganese, which means each of its allotropes has a different crystal form and molecular structure. Therefore, each allotrope exhibits different chemical and physical properties (see the forms of carbon—diamond, carbon black, and graphite). The alpha (a) allotrope is stable at room temperature whereas the gamma (y) form is soft, bendable, and easy to cut. The delta A allotrope exists only at temperatures above 1,100°C. As a pure metal, it cannot be worked into different shapes because it is too brittle. Manganese is responsible for the color in amethyst crystals and is used to make amethyst-colored glass. 

When well-formed individual crystals have been obtained, filter them on a Witte plate, wash once with dilute nitric acid (1 3), pump as dry as possible, place the moist crystals in a suitable vessel, and put this in a desiccator over sulfuric acid. Watch the crystals carefully, with occasional stirring, and bottle them at once when they are dry. Do not touch them with the fingers, as this will discolor them. If they are allowed to overdry in the desiccator, they lose both crystal water and nitric acid and turn into a sticky mass of brownish-colored basic salt, which will not take up water from the air to reverse the reaction. Consequently, effloresced crystals cannot be used to complete the drying of the moist crystals. If the crystals are exposed to moist air, they deliquesce, undergo hydrolysis in the resulting solution, and form a basic salt. If they are bottled before they are dry, they will in time become discolored. If properly prepared, they will remain perfectly transparent and have a very pretty amethyst color, the intensity of which depends upon the size of the crystals. Crystals of iron alum have the same color. 

Large, pale violet (amethyst colored), transparent, octahedral crystals, soluble in 2 parts of water and insoluble in alcohol. The aqueous solution has an acid reaction. 

Colorless crystals of 2,3,4,4-tetrachloro-l-oxodihydronaphthalene (P-TKN), 38) assume an amethyst color upon UV irradiation. This photochromic behavior of p-TKN was initially explained39 in terms of the reversible photochemical dissociation of the ketone into a trichloronaphthoxyl radical and a chlorine atom ... 

Uranium is deposited on the negative electrode in the electrorefining phase of fuel reprocessing. The crystalline mass is about 97% LiCl and KCl. The remaining 3% uranium chloride is responsible for the amethyst color. 

Manganese. Manganese is a hard but very brittle, paramagnetic metal. Mostly it is used in steel alloys to increase strength, hardness, and abrasion resistance. It can be combined with aluminum and antimony to form ferromagnetic compounds. It is used to give glass an amethyst color, in fertilizers, and in water purification. 

Mosander continued to study the properties of lanthanum and determined its atomic weight. During this work he made some observations that confused him. The oxide was brick-red but the color altered from experiment to experiment. In 1840 Mosander made some very important investigations of the amethyst-colored solution of lanthanum sulfate. He discovered that the sulfate was more soluble in cold water than in warm. He prepared a concentrated solution at 9°C. When he heated this so-... 

Thiocyanate and metallic zinc, added to a concentrated HCl mixture with W, give a deep green color. If the SCN is added to W04 then HCl, and finally Zn, a beautiful amethyst color results. 

As a coloring oxide in lead potash glasses, manganese produces an amethyst color, while in soda glass a reddish-violet is produced. 

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