SPECULARIS Lapis, in natural history, a genus of talcs, composed of large plates visibly separate, and of extreme thinness; and each fissile again separated into a number of plates still finer. (See TALC.) Of this genus there are three species: 1. The white shining specularis, with large and broad leaves, commonly called ijinglits and Myscow glas; its lamellae, or leaves, are extremely thin, elastic, and transparent; it makes not the least effervescence with aquafortis, and is not easily calcined in the fire. It is imported in great quantities; the miniature-painters cover their pictures with it; the lantern-makers sometimes use it instead of horn; and minute objects are usually preserved between two plates of it, for examination by the microscope. 2. The bright brown specularis, with broad leaves; a very valuable species, though inferior to the former. 3. The purple bright specularis, with broad leaves, which is the most elegant of all the talcs, and not less beautifully transparent than the first kind.