Cliap. 19.] TANOS. 413 



far from distinctly pronounced, they resembled in their tints 

 the feathers that are seen in the tail of the peacock or on the 

 necks of pigeons.*^* More or less brilliant, too, according to the 

 angle at which they were viewed, they presented an appearance 

 like that of veins and scales. There was another defect, also, 

 peculiar to these stones, known as '' sarcion," from the circum- 

 stance that a kind of flesh*' appeared to attach itself to the 

 stone. The mountain near Chalcedon, where these stones were 

 gathered, is still known by the name of '' Smaragdites." Juba 

 informs us that a kind of smaragdus, known as *' cloras,"*^ is 

 used in Arabia as an ornament for buildings, as also the stone 

 which by the people of Egypt is called '' alabastrites." On the 

 same authority, too, we learn that there are several varieties 

 of the smaragdus in the neighbouring mountains, and that 

 stones like those of Media are found in Mount Taygetus,*^ as 

 also in Sicily. 



CHAP. 19. — THE PRECIOTJS STONE CALLED TANOS. CHALCOSMA- 

 EAGDOS. 



Among the smaragdi is also included the precious stone 

 known as " tanos."^* It comes from Persia, and is of an 

 unsightly green, and of a soiled colour within. There is the 

 chalcosmaragdos^^ also, a native of Cyprus, the face of which is 

 mottled with coppery veins. Theophrastus relates that he 

 had found it stated in the Egyptian histories, that a king of 

 Babylon once sent to the king of Egypt a smaragdus'*^ four 



*"* Said Tfith reference to Chrysoprase, Ajasson thinks ; a leek- green 

 chalcedony, coloured by nickel. 



*^ Probably the Cacholong of modern mineralogy, a variety of opal, 

 nearly opaque, and of a porcelain or bluish white colour. 



^2 Ajasson and Brotero identify this with milk-white chalcedony ; but 

 on what authority, does not appear. 



« See B. iv. c. 8. 



*•* Supposed by Ajasson to be the Euclase, a brittle green stone, com- 

 posed of silica, alumina, and glucina. Haiiy gave it this name from the 

 Greek words tv, " easily," and kXcioj, " to break." According to Dana, 

 however, Euclase was first brought from Peru : if such is the fact, we must, 

 perhaps, look for its identification in Epidote, a green silicate of alumina. 



^5 " Brazen smaragdus." It was probably Dioptase, combined with cop- 

 per Pyrites. See Notes 26, 28, and 29, above. 



^6 \Vith reference to this statement and the others in this Chapter, 

 Ajasson remarks that these stones can have been nothing but prases, green 

 jaspers, fusible spaths, emerald quartz, and fluates#f lime. 



