O. A. Derby — Notable Brazilian Diamond. 191 



Art. XXI. — A Notable Brazilian Diamond; by Orville 



A. Derby. 



A diamond of large size and of certain interesting peculiar- 

 ities of form and surface recently appeared in Eio de Janeiro 

 from the river Bagagem district, in the southwestern part of 

 the state of Minas Geraes, in the headwater region of the river 

 Parana. This district, in which diamonds were first discovered 

 about the middle of the last century, became famous in 1S53 

 through the finding of a stone that took the name of Star of 

 the South and which is until to-day the largest well authen- 

 ticated diamond known from Brazil. Its weight in the rough 

 is given as 52'276 grams, or 2514 Paris carats ( = 255 inter- 

 national carats), if was found in or near the river Bagagem, a 

 few kilometers below the town of the same name, and a few 

 months later and in about the same place a second large stone, 

 known as the Dresden diamond, was found which weighed in 

 the rough 119*5 carats or 24-1172 grams. The present 

 stone, to which the name of Estrella de Minas (Star of Minas) 

 has been given and which weighs 35 - S754 grams (175 inter- 

 national carats of 205 milligrams), is reported to have come from 

 or near the same spot.* 



The shape and size of the present stone could be very ap- 

 proximately represented by quartering an elliptical rubber ball 

 representing a medium-sized hen's egg, and then distorting 



* The upper Parana diamond field and the neighboring one of the river 

 Abaete on the opposite side of the Parana-Sao Francisco watershed are the 

 only ones in Brazil that have afforded diamonds of over 100 carats weight. 

 In the older Diamantina field, which has been worked continuously since 

 1T28. a stone of an oitava (an eighth of an ounce, the most frequently used 

 Portuguese unit for precious metals and stones) was considered such a rarity 

 that in the days of slave labor liberty was given to the finder. Apparently 

 only some scores, or at most a few hundreds, of such stones were found in 

 this field, and those of a weight of 50 to 100 carats can be counted on the 

 fingers. The same is the case in the productive Bahia field, in which, how- 

 ever, black diamonds or Carbonados of hundreds and even thousands of 

 ear.tts (the largest known weighed 3148 carats or about 120 carats more than 

 the famous Cullman diamond) appear. According to information that is 

 considered reliable, the largest diamond ever found in Brazil was destroyed 

 in 1906 by the stupid sledge and anvil test for hardness. It was found in 

 the river Terissimo district in southern Goyaz adjacent to the Bagagem 

 district and is reported to have been of about the size and shape of an 

 ordinary matchbox, that is to say a parallel opipidon of 60x36x16 milli- 

 meters. On this basis its weight was calculated as over 600 carats, or 

 roughly between two and three times that of the Star of the South. A 

 parcel of powder and fragments which one of the interested parties had 

 saved as his share was shown me by a local lapidary who had taken pains to 

 gather reliable information regarding the matter. The parcel when pur- 

 chased by him contained something over 100 carats and from the largest 

 fragment he cut a stone of 8 carats. 



