GEM COLLECTION. 271 



TjTol. This gem shows the pUiy of colors peculiar to the diamoiul. 

 Specimens have also been found at Bridgewater Station, Pa. There are 

 two long andalusites of 1 and 2 carats' weight, stones which are at times 

 so dichroic that they have been ottered in London as Alexaudrites ; 

 also a square brilliant cut stone of 1 carat. No stones in this collection 

 show the dichroic property to the visitor so perfectly as these, they 

 being so cut as to show the red and green colors at once from the same 

 point of view. These are from Brazil, where fine green ones are also 

 obtained. 



Next in order are four light-green diopsides from De Kalb, N. Y., a 

 locality which has yielded 20-cara.t gems, of rich oil-green color, equal to 

 the 2^ carat cut-stone from Ala., in Piedmont. 



A small, long, 1-carat kyanite, from Russia, is noteworthy, as is also 

 the suite of opals, consisting of two noble cut stones, from Hungary, 

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

 mottled with opalescent spots ; a set of over twenty gems, white, yel- 

 low, and brown, from (^ueretaro, JNIexico, and two milky opals without 

 the play of colors, from Honduras, an inch and an inch and a half long, 

 respectively ; three pieces of blue opal, in the impnre brown limonite, 

 or ironstone matrix, from the Baricoo River, Queenshuid, Australia, 

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



Of turquoise, we have a bluish-green piece H inches long, cut into a 

 flat cabochon stone, from Los (Jerillos, New Mex., a fine suite of the 

 uiineral in the matrix, recently brought on by Maj. J. W. Powell, from 

 New Mexico, and a set of twenty-four gems from Persia, showing all the 

 cbaracteristic gradations of color between blue and green ; a curious 

 three quarter-inch cabochon cut stone, and a ]uece 1| inches long in the 

 Rjatrix, from Persia, noticeable for the pleasing contrast of the bluish- 

 green stone on the background of chocolate color. A handsome suite, 

 consisting of a l-inch flat cabochon and seven polislied si)ecimens of 

 turquoise in the matrix, from Los Cerillos, New Mex., has lately been 

 deposited by Mr. Thomas Donaldson, of Philadelphia. These vary in 

 color from the malachite-green to the rich light-blue, and in size from 

 1 by 2 l)y 3 inches to .'> by 1 by inches. 



Hematite is exhibited, cut in the form of a ball and in a cut intaglio. 

 Dis[)layed near these is a <;ut 1-carat riitile, from Alexander County, 

 N. 0. This so closely rcsend>Ies the black diamond in color and luster 

 as to have been mistaken for it when first found. A large rhodonite, 

 cut en eahochon, is on the same pad with these specimens. 



A dark, almost black, hyi)ersthene irom Norway shows a pleasing 

 bronze-like reflection on the dome of the cabochon, while a polished 

 slab of lighter color is Jilso quite attractive. Chlorastrolite is repre- 

 sented by three small polished pebbles from Isle Jioyale, Lake Superior. 

 One of the most instructive of the series is a quantity of gem-gravel 

 from Ceylon, containing sapphires of various colors, (;hrysoberyl, zircon, 

 quartz, and other stones. 



