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HISTORICAL PROJECTS

San Gregorio, Uruguay

As reported, effective October 1, 2003, Crystallex sold its Uruguayan interests, including the San Gregorio mining operations to Uruguayan Mineral Explorations Inc, (UME).

Under the terms of the agreement, UME paid Crystallex US$2 million in two equal installments, with the first installment six months after closing and the second installment twelve months after closing. Formal closing was completed on October 27, 2003. Crystallex also received a transfer of certain exploration drilling equipment, with an estimated value of US$600,000. In addition, UME paid approximately US$2.8 million to fund the closing out of all remaining San Gregorio gold forward sales commitments, (approximately 37,600 ounces), and through the Uruguayan companies purchased, assumed certain environmental, remediation, severance and closure costs which would have been incurred by Crystallex had it proceeded with the planned closure of its Uruguayan mining operations.

The sale was completed through the transfer of the shares of the Company’s Uruguayan subsidiary companies which owned the mining assets. The Company recorded a non-cash $2.0 million loss as a result of this transaction.

 

San Gregorio Operating Performance

 

100% Basis

20031

2002

2001

San Gregorio
(100% Crystallex)

 

 

 

Tonnes Ore Mined

739,000

1,062,626

828,526

Tonnes Waste Mined

3,284,000

4,685,190

5,007,753

Tonnes Ore Processed

760,000

1,105,619

1,092,389

Average Grade of Ore
Processed (g/t)

1.86

2.04

2.09

Recovery Rate (%)

92%

92%

91%

Production (ounces of gold)

41,729

66,832

66,957

Total Cash Cost Per Ounce

$276

$237

$262

1 Figures are for the nine months of 2003 that Crystallex owned San Gregorio.




Tomi, Venezuela

The Tomi concession is located approximately 16 km northeast of the town of El Callao in the El Callao District, Bolivar State, Venezuela. El Callao is a three-hour drive south from Puerto Ordaz, the largest city in Bolivar State. The Tomi property is accessible via an all-weather, northbound dirt road that exits from Highway 10 about 10 km from El Callao. Ore from Tomi is trucked approximately 21 km to the Revemin mill for processing. All necessary infrastructure exists at the Tomi concession since the open-pit mines have been in operation since August 2000.  There are four adjoining deposits on the concession, namely Charlie Richards, Mackenzie, Milagrito and Fosforito. Mining commenced in 1998 at the Mackenzie open pit, and subsequent to Crystallex’s purchase of the concession in August 2000, mining has also been conducted in the Charlie Richards and Milagrito open pits. In 2001, Crystallex completed a diamond drill program and Feasibility Study (completed by Mine Development Associates) which supported the development of an underground mine below the Charlie Richards pit.

Over the course of 2002 and the first half of 2003, a small, high grade underground mine was developed and gold production commenced in the second half of 2003.  In 2007, the Tomi operations consisted of two active open-pit mines (McKenzie and Fosforito) and one underground mine (Charlie Richards).

Production from the Tomi deposits was 21,988 ounces in 2007, a 47% decrease from 41,638 ounces produced in 2006. Lower production in 2007 primarily reflects the near depletion of the Mackenzie and Fosforito open pit deposits (as evidenced by higher strip ratios and lower ore grades), coupled with fewer tonnes mined from underground due to poor drill availability. The strip ratio (the ratio of waste mined to ore mined) at the Tomi open pits increased to 16.0:1 in 2007, up from 10.0:1 in 2006 and 6.3:1 in 2005. The higher strip ratios are due to mining from deeper pits and the timing of the push back of the pits, which resulted in removing most of the waste in 2007 to uncover ore to be mined in 2008. Only 96,000 tonnes of ore were mined from the Tomi open pits in 2007, as compared with 228,000 in 2006, (however this was partially offset by increasing the mining rate at the La Victoria deposit – see La Victoria Project). 

  • In 2007, a 32-hole diamond drilling program totalling 4,443 m was completed at Fosforito, La Fortuna and Milagrito East. A 54-hole reverse circulation drilling program totalling 5,999 m was also undertaken at Fosforito. The Tomi Underground Mine had an additional 26 diamond drill holes totalling 3,211 m completed in 2007; and
  • Two programs of geophysics (microgravity) were completed in western and south-eastern Tomi in 2007.


Tomi Operating Highlights

100% Basis

2007

2006

2005

Tomi Open Pits (100% Crystallex)

 





Tonnes Ore Mined

95,629

227,845

313,599

Tonnes Waste Mined

1,531,589

2,287,217

1,971,402

Tonnes Ore Processed

105,126

211,936

319,287

Average Grade of Ore
Processed (g/t)

2.8

3.1

3.2

Recovery Rate (%)

90%

94%

93%

Production (ounces)

8,437

19,428

30,290

Tomi Underground (100% Crystallex)

 

 

 

Tonnes Ore Mined

61,031

89,689

72,177

Tonnes Ore Processed

65,334

88,183

63,319

Average Grade of Ore
Processed (g/t)

7.0

8.4

10.2

Recovery Rate (%)

92%

93%

95%

Production (ounces)

13,551

22,210

19,811





La Victoria, Venezuela

La Victoria is the largest of six deposits on the Lo Increible property - a northeast trending zone of scattered gold mineralization located immediately north of the town of El Callao in the historic El Callao gold district, Bolivar State, Venezuela.  ocated in southeastern Venezuela in the historic El Callao gold district.  Crystallex acquired its 51% interest in Lo Increible in 2001 and commenced open pit mining at La Victoria in April of that year.  Ore from the La Victoria mine, located on the Lo Increíble property, is delivered to the Revemin mill for processing.

Initial metallurgical testwork on the La Victoria sulphide ore deposit demonstrated that the content of refractory ore was higher than originally estimated, and as a consequence a significant portion of the sulphide ore cannot be economically processed using the conventional cyanide gold extraction process at the Revemin mill. The gold in the La Victoria ore is encapsulated in sulphide minerals which prevent sufficient quantities of gold from being exposed to cyanide, and thus results in low gold recovery. Bench scale testwork at SGS Lakefield Research indicated that the ore at La Victoria is very amenable to Bio-Oxidation (BIOX), a pre-treatment step that breaks down the sulphide minerals through accelerating the oxidation process, thereby exposing the gold for subsequent removal by cyanide leaching.

During the fourth quarter of 2003, the Corporation reduced activities at La Victoria as a result of significantly lower recovery rates due to the presence of refractory ore. With the increase in gold prices in 2006 and 2007, the Corporation restarted mining activities at La Victoria. In addition, the mine’s economics were improved by averaging a 75% gold recovery rate in 2007, as compared with the 68% average for the first three quarters of 2003 prior to reducing activities at the mine.


La Victoria Operating Highlights

100% Basis

2007

2006

2005

La Victoria

 





Tonnes Ore Mined

128,676

64,222

24,892

Tonnes Waste Mined

557,657

353,052

126,704

Tonnes Ore Processed

125,903

51,424

25,649

Average Grade of Ore
Processed (g/t)

2.9

2.3

2.0

Recovery Rate (%)

79%

86%

89%

Production (ounces)

9,356

3,260

1,419