that in cutting Topaz for a gem a cleav- 

 age surface is used as the upper face of 

 the gem and the other faces formed 

 around it. Owing to this easy cleavage 

 the owner of a cut Topaz should be care- 

 ful not to let the stone drop, as it might 

 be cracked or broken. 



The name Topaz is derived from the 

 Greek name topazios, which is that of 

 an island in the Red Sea. The gem 

 known to the ancients as topaz, however, 

 was not our Topaz, but the mineral chry- 

 solite. Topaz usually occurs in gneiss 

 or granite, with tourmaline, mica, beryl, 

 etc. In Brazil it occurs in a talcose rock 

 or in mica slate. It is sometimes in suf- 

 ficient abundance to form an essential 

 rock constituent. When so occurring, 

 however, it has not the transparent gem 

 quality, but is white and opaque. Much 

 of the Brazilian Topaz occurs as rolled 

 pebbles, one of which is shown in the 

 accompanying plate. These occur in the 

 beds of streams, having been left behind 

 owing to their superior hardness after 

 the rock in which they were formed has 

 been washed away. When colorless 

 they are known in the region as "pingos 

 d'Agua" (drops of water). The Portu- 

 guese call them "slaves' diamonds." A 

 stone in the crown of Portugal, reputed 

 to be a diamond of 1,680 carats weight 

 and called the Braganza, is undoubtedly 

 only a Topaz of exceptional clearness and 

 beauty. 



The Brazilian Topazes come mostly 

 from the Province of Minas Geraes, the 

 province which also yields diamonds, 

 beryls and many other precious stones. 

 While those of greenish and bluish 

 shades are found mostly in the form of 

 rolled pebbles the yellow Brazilian Topaz 

 is found in the mother rock. This is a 

 decomposed itacolumite of a white or 

 yellow color. The Russian Topazes, like 

 that shown in the plate, come from the 

 Imperial mines in the Urals. Alabashka, 

 near Mursinka, is one of the most pro- 

 ductive localities. The crystals occur in 

 cavities in granite and are accompanied 

 by crystals of smoky quartz, feldspar 

 and mica. Superb gems are cut from 

 these Topazes, a fine series of which is 

 possessed by the Field Columbian Mu- 

 seum. The mines are operated by the 

 Russian Government and the finest spec- 



imens are reserved for the Imperial Cab- 

 inet. 



In the southern Urals, in the gold 

 washings of the River Sanarka, yellow 

 Topazes are found closely resembling 

 those of Brazil. Associated with them 

 are amethysts, rubies, chrysoberyls and 

 many other precious stones. Topaz crys- 

 tals of good size and color are found 

 quite abundantly in Japan, although they 

 have not yet been cut for gems to any 

 extent. There are many localities in the 

 United States where Topaz occurs, and it 

 is often of gem quality. The group 

 shown in the plate illustrates its occur- 

 rence at Thomas Mountain, Utah, a lo- 

 cality forty miles north of Sevier Lake. 

 The crystals are found in cavities in the 

 rock. They are never very large, but 

 are usually clear and bright. They oc- 

 cur in somewhat similar fashion at Na- 

 throp, Colorado. In the Eastern States 

 Topaz was first found at Trumbull, Conn. 

 It is here quite opaque and not suitable 

 for gem purposes. Good gem Topaz has 

 been found at Huntington and Middle- 

 town, Conn., however, and especially at 

 Stoneham, Maine. In these localities it 

 occurs in granite. 



Of other stones which are sold under 

 the name of Topaz the most common is 

 the so-called Spanish or Saxon topaz. 

 This is simply smoky quartz heated un- 

 til it turns a yellow color. It can easily 

 be distinguished from true Topaz by the 

 properties above given. 



At the present time it is also quite the 

 common practice to vend ordinary color- 

 less quartz under the name of Topaz. 

 These practices are harmful to the repu- 

 tation of true Topaz, as these forms of 

 quartz are common and cheap and lack 

 many of the desirable qualities of that 

 stone. There is also a so-called Orien- 

 tal' Topaz which is a yellow form of co- 

 rundum. It is heavier and harder than 

 true Topaz, but its color and luster are 

 not generally considered as desirable as 

 those of that mineral. About forty years 

 ago Topaz was quite popular as a gem 

 and commanded three or four times its 

 present price. At the present not more 

 than two dollars a carat is often paid for 

 the stone. 



Topaz is often referred to by ancient 

 writers and is mentioned in the Bible as 



219 



