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 as necklaces, &c. but more generally in seals and brooches. Stones sufficiently large for this purpose, may be purchased at from five to ten or fifteen shillings each, and inferior for considerably less.

substance has also been lately imported in large quantities from Brazil, which has so overstocked the market, that it is now selling at from fifteen shillings to two guineas per pound; whereas a few years ago it sold for three guineas per ounce: it is a beautiful stone, and will most likely become more valuable.—It is often set on foil, and sold for topaz, which it much resembles, but is less brilliant.

ROCK CRYSTAL

a transparent substance proverbially clear. It occurs massive and crystallized, filling veins and crevices of rocks; also in rolled pieces in