I 



54 



closed in a grey quartz, which serves them for a ma- 

 trix, and others isolated among the sand. They are 

 more perfect both in colour and hardness in propor- 

 tion to their depth, and were those who search for 

 them to dig deeper, they would, most probably, dis» 

 cover them in the highest state of perfection. A 

 short time before I left Chili I saw some that were 

 of a beautiful violet, and would cut glass repeat- 

 edly without injuring their points. Among them, 

 were a few of as fine a water as the diamond, and 

 perhaps they may serve as precursors to that most 

 valuable gem. They are so abundant that, in some 

 of the crevices of the rocks, those of a fine purple ^ 

 may be discovered at almost every step. 



The province of Copiapo owes its name, accord- 

 ing to the Indian tradition, to the great quantity of 

 turquoises found in its mountains. Though these 

 stones ought, with propriety, to be classed among 

 the concretions, as they are only the petrified teeth 

 or bones of animals, coloured by metallic vapours, 

 J have thought proper to mention them here, as they 

 are placed by many among the precious stones. The 

 turquoises of Copiapo are usually of a greenish blue, 

 some, however, are found of a deep blue, which are 

 very hard, and known by the name of the turquoises 

 of the old rock. 



Mixed stones, or those formed by the combina- 

 tion of several heterogeneous substances, are here, 

 as elsewhere, the most numerous, and form a con- 

 siderable portion of the Chilian mountains. Beside 

 the com.nion stones of this class, various kinds of 



