I) I amoks'D. 
13D 
composition. And the same group admits of the addition of a numerous 
class of substances, of an inflammable character, partaking more or less 
of the nature of mineral pitch and resins. 
Nos. 1 to 11. A series of Spe- 1 
cimens illustrating the mode of 
occurrence of the Diamond, its 
varieties of colour, its uses, and 
the methods of cutting and polish¬ 
ing. 
O 
From Brazil. 
Presented by E. Z. Dresden. 
1. Cascalho, a gravel com¬ 
posed of quartz pebbles with fer¬ 
ruginous clay, and according to 
its constituents considered an 
indication of the presence of 
diamonds. 
2. Carbonado, an amorphous 
variety of diamond : two pieces, 
weighing 16 grains. 
3. Bort or Boort, weighing 
grains, a dark and confusedly 
crystalline variety of diamond, 
valuable as a polishing material. 
Brazil. 
4. Pure Diamond Powder, 
weighing 12 grains. 
5. Part of a rough Diamond 
(“ diamantina quality ”), weighing 
grains, split from a stone in 
consequence of an imperfection. 
6. Splintered rough Diamond, 
weighing 5^ grains. 
7. Two small Diamonds, used 
by glaziers for cutting glass. 
8. Four Rough Diamonds, 
weighing 12 grains. 
9. Six Rough Diamonds, 
weighing 13 grains. 
From the Sincura Mines, Province 
of Bahia. 
10. Rough Diamond, weighing 
3^ grains, the four points of which 
have been cut, being the first stage 
in the process of cutting before 
polishing. 
11. Five CUT Diamonds, of 
which four are Brilliants, and one 
Rose cut. 
12. T'ablet supporting six na¬ 
tural crystals of Diamond. 
Brazil. 
13. Black Diamond, cut as a 
brilliant. 
14. Bort, or “ Diamond of 
Nature,” an impure variety used 
for drilling, polishing, &c. This 
specimen is fractured to exhibit 
its radiated internal structure. 
Brazil. 
15. Carbonado, or “Carbo¬ 
nate,” an amorphous variety of 
diamond, used for drilling, &c. 
Brazil. 
Presented by J. Moring. 
16. Tablet supporting six 
Models in paste, to illustrate 
the forms in which gems are cut, 
viz. :— 
1 and 2. Brilliants. 
3 and 4. Roses. 
5. Table. 
6. Cabochon. 
17. Models of the Koh-i-noor 
and Pendants, as exhibited in the 
Great Exhibition, 1851. Weight 
of the Koh-i-noor, 186yL carats. 
18. Models of the Koh-i-noor 
and Pendants, in their present 
state. Weight of the Koh-i-noor, 
102^ carats {Tennant). 
19. Model of the blue Hope 
Diamond, in the collection of the 
late Mr. P. PI. Plope, weighing 
177 grains {Hertz), and valued at 
30,000/. 
20. Model of the Orloff, or 
Grand Russian Diamond, weigh¬ 
ing 194J carats {Kluge). Sold 
for about 90,000/. and an annuity 
of 4,000/. {Mawe). 
21. Model of the Austrian, 
Maximilian, or Grand Tuscan 
Diamond, weighing 139^ carats 
{Kluge), and valued at 109,250/. 
{Feuclitio anger). 
