HIDDENITE, a green transparent variety of spodumene, (q.v.) used as a gem-stone. It was discovered by William E. Hidden (b. 1853) about 1879 at Stonypoint, Alexander county, North Carolina, and was at first taken for diopside. In 1881 J. Lawrence Smith proved it to be spodumene, and named it. Hiddenite occurs in small slender monoclinic crystals of prismatic habit, often pitted on the surface. A well-marked prismatic cleavage renders the mineral rather difficult to cut. Its colour passes from an emerald green to a greenish-yellow, and is often unevenly distributed through the stone. The mineral is dichroic in a marked degree, and shows much "fire" when properly cut. The composition of the mineral is represented by the formula LiAl(SiO3)2, the green colour being probably due to the presence of a small proportion of chromium. The presence of lithia in this green mineral suggested the inappropriate name of lithia emerald, by which it is sometimes known. Hiddenite was originally found as loose crystals in the soil, but was afterwards worked in a veinstone, where it occurred in association with beryl, quartz, garnet, mica, rutile, &c. HIDE[1] (Lat. _hida_, A.-S. _higid_, _hid_ or _hiwisc_, members of a household), a measure of land. The word was in general use in England in Anglo-Saxon and early English times, although its meaning seems to have varied somewhat from time to time. Among its Latin equivalents are _terra unius familiae_, _terra unius cassati_ and _mansio_; the first of these forms is used by Bede, who, like all early writers, gives to it no definite area. In its earliest form the hide was the typical holding of the typical family. Gradually, this typical holding came to be regarded as containing 120 "acres" (not 120 acres of 4840 sq. yds. each, but 120 times the amount of land which a ploughteam of eight oxen could plough in a single day). This definition appears to have been very general in England before the Norman Conquest, and in Domesday Book 30, 40, 50 and 80 acres are repeatedly mentioned as fractions of a hide. Some historians, however, have thought that the hide only contained 30 acres or thereabouts.