Search the Dictionary

A silicate of alumina, iron, and magnesia, having a bright blue color and vitreous luster; cordierite. It is remarkable for its dichroism, and is also called dichroite.

A fossil coral of the genus Heliolites, having twelve-rayed cells. It is found in the Silurian rocks.

The same Milliolitic. Miliolite limestone (Geol.), a building stone, one of the group of the Paris basin, almost entirely made up of many-chambered microscopic shells.

A hippurite.

Meerschaum. See Meerschaum.

One of the microsporic siliceous spicules which occur abundantly in the texture of sponges, and are sometimes found fossil, as in flints.

A kind of diorite or diabase containing imbedded whitish spherules, which give the rock a spotted appearance.

See Iolite.

Iolite; -- so called from its presenting two different colors when viewed in two different directions. See Iolite.

A hydration of iolite.

y in Asia Minor. It is manufacturd into tobacco pipes, cigar holders, etc. Also called sepiolite.

Of or pertaining to the genus Miliola; containing miliolites.

A variety of iolite, of a smoky blue color; pelioma.

is a hydrous alkaline silicate, and is derived from the alteration of other minerals, as iolite.

A variety of altered iolite of a green color and greasy luster.

(Geol.) A spherule of a variolite.

Of, pertaining to, or resembling, variolite.

A deep blue variety of iolite, sometimes used as a gem; -- called also saphir d'eau.