1911 Encyclopædia Britannica/Moldavite

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MOLDAVITE, an olive-green or dull greenish vitreous substance, named by Dufrénoy from Moldauthein in Bohemia, where it occurs. It is sometimes cut and polished as an ornamental stone under the name of pseudo-chrysolite, Its bottle-glass colour led to its being commonly called Bouteillenstein, and at one time it was regarded as an artificial product, but this view is opposed to the fact that no remains of glass-works are found in the neighbourhood of its occurrence: moreover pieces of the substances are widely distributed in Tertiary and early Pleistocene deposits in Bohemia and Moravia. For a long time it was generally believed to be a variety of obsidian, but its difficult fusibility and its chemical composition are rather against its volcanic origin. Dr F. E. Suess pointed out that the nodules or small masses of moldavite presented curious pittings and wrinkles on the surface, which could not be due to the action of water, but resembled the characteristic markings on many meteorites. Boldly attributing the material to a cosmic origin, he regarded moldavite as a special type of meteorite for which he proposed the name of tectite (Gr. τηκτός, melted). To this type are also referred the so-called obsidian bombs and buttons from Australia and Tasmania, known sometimes as australite, and called by R. H. Walcott obsidianites. Similar bodies have been found in Malaysia and have been termed billitonite, from the isle of Billiton where they occur in tin-bearing gravels. Usually they are flat, rounded or ellipsoidal bodies, sometimes surrounded by an equatorial girdle or rim, and often with a brilliant black superficial lustre, as though varnished. Moldavite has been reported also from Scania in Sweden.

See Franz E. Suess, Jahrbuch der k.-k. geolog. Reichsanstalt (Vienna), 1901, p. 193; E. Weinschenk, Centralblatt f. Mineralogie (Stuttgart), 1908, p. 737. (F. W. R.*)