石綿

化学的特性TREMOLITE, the mineral tremolite is a calciummagnesium silicate corresponding to the formula Ca2Mg5Si8O22(OH)2, belonging to the amphibole group. The replacement of magnesium by ferrous iron causes tremolite to approach actinolite in composition. Tremolite is monoclinic, developing bladed prismatic crystals, but it is frequently found in compact columnar, granular, or fibrous masses. The perfect prismatic cleavage at angles of 56° and 124° typical of this group is to be noted; hardness, 5–6; specific gravity, 2.9–3.1; luster, vitreous to silky; color, varies from white or whitish-gray through shades of green or greenish-yellow; transparent to opaque. Tremolite is formed as a result of contact metamorphism and occurs in marbles, dolomites, and schists. It may alter to talc.

解説石綿，アクチノセン石，アクチノ角セン石，緑セン石あるいは陽起石ともいう。カルシウム角セン石の一つで，化学組成はCa2(Mg,Fe2＋)55Si8O22(OH)2で表される鉱物。ふつうMg/(Mg＋Fe2＋)の比が0.5～0.89のものをアクチノセン石，0～0.49のものを鉄アクチノセン石ferroactinolite,0.9～1.0のものを透セン石と呼ぶ。MgとFeは任意に混ざり合う。Mg,Fe2＋やSiを置き換えてAlを少量含むことがある。

説明Asbestos is a fibrous silicate of magnesium and calcium. However, the “extender”, known as “asbestine”, that has come to the forefront in paint making, is really a ring silicate of magnesia and slightly alkaline, but without the fibrous texture of asbestos or amianth. Asbestine pulp (as a certain variety of the material mined at the foot of the Adirondack mountains is known to the trade), although it is sold in the dry powdered form, belongs really to the soapstone or talc variety. But it is not as unctuous as either of those, has a harder texture, and is of whiter color than either soapstone or talc.

使用Asbestine pulp or asbestine in its various varieties has been used for many years by manufacturers of paints, not so much as an adulterant, but rather to make the paint more buoyant in order to keep it from settling to any extent, as this compound is of very low-specific gravity and a great oil absorber.

一般的な説明Any of a group of impure magnesium silicate minerals that occur as slender, strong, flexible fibers. Colors range from white to gray, green, brown. Resistant to fire and most solvents. Breathing of ASBESTOS dust causes ASBESTOSis and lung cancer. Used as a heat resistant material, in cement, furnace bricks, and in brake linings.

定義A fibrous variety of various rock-forming silicate minerals, such as the amphiboles and chrysotile. It has many uses that employ its properties of heat-resistance and chemical inertness. Prolonged exposure to asbestos dust may cause asbestosis – a form of lung cancer.