The word SELENITE is derived from the Greek SELENE, the moon, and is found also written as silenite, silonite, silenitis. The stone which is a crystallized variety of gypsum is in pearly white, green, yellow and gray colours. Marbodus compares it with soft grass or verdant jasper, and Malpleat, in 1567, says it is like a fresh and flourishing green herb. The moon-like lustres whether in pearl-white or light green are the most esteemed, and Pliny writes that it is frequently employed in the construction of beehives to enable the curious to watch the little insects at their wonderful work. The ancients employed it in much the same way as we do glass, and it formed an item of considerable trade importance between Rome, Spain, Cyprus, Africa, Cappadocia and other parts of the ancient world. Slightly coarser varieties were used by Tiberius to cover his hot-houses, for it is susceptible of being split into comparatively thin sheets. A finer variety of very great value was at one time to be seen in the palace at Pekin. Dr. John Goad, who wrote the Astro-Meteorologia, a book on the natures and influences of the celestial bodies, mentions the Selenite which Pope Clement VIII had amongst his treasures. It was a natural moon dial, of which Cocheram said in 1623, “it decreaseth and encreaseth as the moon groweth.” This Dr. Goad was a famous scholar who, wrote Cooper, “gained a reputation for his astrological knowledge founded on reason and experiment.” The Greeks called the stone Selenitis Lithos, because they said it waxed and waned with the moon, a belief quaintly expressed by Trevisa in 1398 as follows: “Selenites is a stone of Perse, grene as grasse. It shineth with a white specke and foloweth the moon and waxyth and waneth as the moon doeth.” Some old stories tell of a belief that little Moon men which Howell, a 17th century writer, calls “Selenites or Lunary Men,” flung these stones deep in the earth. The Selenite was regarded as a love attractor and a stone to restore harmony between quarrelsome lovers. If engraved with a figure of Diana with bow and arrow when the moon was passing through the 3rd, 16th and 17th degrees of Cancer it increased, say old writers, the power of imagination and helped the wearer to realize future movements. If the Selenite be burned and carefully powdered it is said to be of great use in cleaning pearls (which also are moon-ruled according to astrology). The Selenite is under the sign Cancer like the moonstone, with which it is frequently confounded. SERPENTINE OR HYDRINUS