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Gold/Mining/Energy : SOUTHERNERA (t.SUF) -- Ignore unavailable to you. Want to Upgrade?


To: gemsearcher who wrote (4465)9/7/1999 10:19:00 AM
From: PHILLIP FLOTOW  Read Replies (1) | Respond to of 7235
 
Lifted from a Dow Jones report on DeBeer's earnings:

The bright picture will be clouded by declines in income from its diamonds
and industrial holdings businesses, said analysts.
Diamond profits should only be marginally lower given a 3.0% decline to $326
million in net profit at the two companies that make up the De Beers diamond
marketing and producing group. Anglo owns about 34% of De Beers.
-By Michael Wang, +27-11-726-7903; michael.wang@dowjones.com

PHIL



To: gemsearcher who wrote (4465)9/7/1999 3:23:00 PM
From: russet  Respond to of 7235
 
Some interesting comments about Brazilian diamond mining from a competitor (Diagem) courtesy of m.philli.http://www.diagem.com/brazil.htm

Although the official discovery of diamonds by Sebastino Leme de Prado was made in 1725 records indicate that early than this date gold miners used diamonds as counters in playing cards. A Portuguese official recognized the nature of the gem and sent some to Lisbon for verification. Early samples were cut in Amsterdam and the quality was found to be as fine as that of diamonds produced in India.

The first diamonds in Brazil were discovered on the Rio dos Marinlios, in the state of Minas Gerais. In 1790 additional discoveries of diamonds occurred northeast of Cuiaba, in Mato Grosso State. Production of diamonds in Brazil increased so dramatically that world diamond prices declined by 75%. The Portuguese government declared diamond mining a Royal monopoly and slowed the production of diamonds in Brazil to a drizzle.

Diamondiferous kimerlites were not discovered until 1968 by a team of Brazilian and French geologists.

In the 265 year period to 1990 47,100,000 carats of diamonds have been produced in Brazil. All of this production has been from alluvial sources and most was produced by garimpeiros.


Much of the Brazilian rough diamond production has been of the octahedral shape and lent itself to the "triple cut" or "old mine cut", a forerunner of the modern "brilliant cut" with 33 crown facets and 25 pavilion facets.

To this day, Brazil is internationally regarded as a country that has unlimited potential in the area of diamond prospecting.

25% OF THE WORLD'S LARGEST ROUGH GEM DIAMONDS HAVE BEEN PRODUCED IN BRAZIL

(Information taken from "Diamonds (second edition) Eric Bruton FGA)
Rank Carats Name Date Cut Into
6 726.6 Vargas 1938 Vargas (48.26ct) + 22 others
12 600.0 Goyaz 1906 8 ct. gem from 1 fragment
20 455.0 Darcy Vargas 1939 Unknown
28 409.0 Presidente Dutra 1946 46 gems (largest 9.06 ct)
29 400.7 Coromandel IV 1941 Unknown
31 375.1 Diario de Minas Gerais 1941 Unknown
33 354.0 Tiros I 1938 Unknown
36 346.2 Unnamed 1948 (a cleavage)
41 328.3 Victoria II 1943 44 gems (largest wt. 30.39 ct)
43 325.0 Unnamed 1948? Unknown
44 324.0 Patos 1957 Unknown