272 POPULAR SCIENCE MONTHLY 



DIAMONDS AND CARBONS IN BRAZIL 



By H. W. FURNISS, 



FORMERLY AMERICAN CONSUL AT BAHIA 



npHE best diamonds of the world, those of finest color and fire, come 

 ■*- from Brazil, though most of the stones mined are small in size 

 as compared with those from other sections. They occur in various 

 places, more particularly Goyaz, Matto Grosso, Minas Geraes and 

 Bahia. It is only in the latter two states in which they have been 

 found in sufficient quantities to warrant mining. 



The exact date of the discovery of diamonds in Brazil is unknown. 

 At the end of the seventeenth century miners were taking out gold 

 in Minas Geraes at Serro Frio and failed to recoguize the diamonds 

 which were occurring therewith. It is said that some stones were 

 collected more because of their regularity and beauty of crystalliza- 

 tion than from knowledge of their value. These in 1729 found 

 their way to Portugal, where they were recognized as diamonds of 

 unusual purity. The discovery caused quite a sensation at the court 

 of King John V. There was a rush to the newly-discovered region, 

 but the king so restricted mining that little was done until subsequent 

 to 1832, when the present laws became effective. 



Diamonds were first discovered in Bahia in 1840 at Santo Ignacio 

 at the extreme northwest of the present region, but not until 1844, when 

 discovery was made by a slave on the banks of the Mocoje river, the 

 present location of Sao Joao do Paraguassii, was any great impetus 

 given to mining. The mining area has gradually extended, but no 

 new section was discovered until 1881 when by accident a find was 

 made at Salobro, the diamonds of which usually take the name of 

 Cannavieiras, the port to which they pay tribute. 



The quality of Brazilian diamonds varies greatly with the locality 

 in which found, while there is always a considerable difference between 

 those of the same mine. In general, those from Minas Geraes are 

 fairly assorted in quality, about Salobro (Cannavieiras) the beautiful 

 whites and priceless blue whites predominate, while the other Bahia 

 stones are inclined to be more off-colored and frequently contain black 

 specks, thereby lowering their value. 



The greater part of the Bahia diamonds differ from those found 

 elsewhere in the world in that they frequently have a thin coat of 

 surface color which gives the Avhole stone a bad appearance. This 

 color will not yield to acids. To one particularly skilled, the under- 



