THE GEMS OF THE NATIONAL MUSEUM. 827 



then sold as diamond-incrusted. Next we observe a fine, rich, hya- 

 cinth-colored gem (the true hyacinth of the mineralogist), a long, two- 

 carat green, a yellowish-green, and a brownish-green three-carat 

 stone, all from Ceylon. The two carat axinite from Dauphiny is one 

 of the rarest of gems. A six-carat yellowish-green epidote from the 

 Knappenwand, the well-known locality in Tyrol, should be mentioned. 



Here, too, is a one-fourth-carat idocrase from Ala, in Piedmont. 

 This mineral, which received the name vesuvianite, because it is found 

 among the formations in the lava at Vesuvius, is sold by the Neapoli- 

 tan jewelers, and used to make the letters I and V in the manufacture 

 of initial or sentimental pieces of jewelry. The same mineral is found 

 at Sandford, Maine, and other localities here, but rarely in gem form, 



lolilite (dichroite, cordierite), or water-sapphire {saphire-d''eau\ 

 as it is also called, is here seen in the form of a flat-cut stone, of two 

 carats' weight, from Ceylon, and a cube, one-fourth inch square, from 

 Bodenmais, Bavaria. These are not comparable with one found at 

 Haddam, Connecticut, that was worn as a charm by the late Dr. Tor- 

 rey. This stone has dichroitic properties : if viewed in one direction 

 it appears blue ; if in another, pure white. 



The five-carat titanite, or yellow sphene, is from the Tavetchthal, 

 in the Tyrol. This gem shows the play of colors peculiar to the dia- 

 mond. Specimens have also been found at Bridgewater Station, Penn- 

 sylvania. There are three long, yellowish-brown andalusites, of two, 

 one, and three-fourths of a carat weight, at times so dichroitic that 

 they have been offered in London as Alexandrites. These are from 

 Brazil, where fine green ones are also obtained. 



Next in order is a light-green diopside, from De Kalb, New York, 

 a locality which has yielded twenty-carat gems, of rich oily-green 

 color, equal to the one-carat cut stone from Ala, in Piedmont. 



A small, long, one-carat cyanite, from Russia, is noteworthy, as is 

 also the suite of opals, consisting of two noble cut stones, from Hun- 

 gary, and a polished slab of the light matrix from the same place, 

 beautifully mottled with opalescent spots ; a set of over twenty gems, 

 white, yellow, and brown, from Queretaro, Mexico ; and two fair, 

 noble opals from Honduras, together with a one-inch, lusterless cut 

 stone ; three pieces of blue opal, in the impure brown iimonite, or 

 ironstone matrix, from the Baricoo River, Queensland, Australia, 

 termed opaline by the jewelers, and also a cut stone from the same 

 locality. 



Of turquoise, we have a bluish-green piece, one inch and a half 

 long, cut into a flat cabochon stone, from Los Cerrillos, New Mexico, 

 a fine suite of the mineral in the matrix, recently brought on by Major 

 J. W. Powell, from New Mexico, and a set of twenty-four gems from 

 Persia, showing all the characteristic gradations of color between blue 

 and green ; a curious half-inch cabochon cut stone, and a piece one 

 inch long in the matrix, from Arabia, noticeable for the pleasing con- 



