Gems Notes and Extracts Augusto Castellani, Mrs. John Brogden 1871

NATROLITE. 151LXY.NATROLITE.THIS mineral has been but recently discovered.It received its name from the Latin natrum, whichmeans soda, because that alkali is its principal component.It has a rough breakage, is translucent at the edges,and of a pearly or white light; sometimes deep red oryellow, and often in alternate zones.It scratches glass with difficulty, but can be markedby felspar.It produces a white powder ; has a specificgravity of 2'16 ;melts under the action of the blowpipe,into a spongy, colourless glass; is composed ofsoda, alumina, silex and water; sometimes a smallquantity of oxide of iron is mixed with it.Natrolite is found in Switzerland, Bohemia, Saxony,Scotland, and Nova Scotia.Natrolite, on account of the polish which it takes,has been used in jewellery, but it was not satisfactory,and now nothingisthought of this gem, so that it hasno value in commerce.LXVI.NEPHRITE.See JADE.