|   TSX: ORA
Operations
Operations

Serrote Mineral Reserves

Serrote Deposit Mineral Reserves for Sulphide Material as of April 10, 2012

Classification1

Material t (x 1,000)

Cu (%)

Au (g/t)

Magnetite (%)

NSR $/t

Proven2, 4

50,805

0.54

0.10

7.09

25.26

Probable2, 3, 4

34,667

0.50

0.09

7.82

22.77

Total Reserves

85,471

0.52

0.10

7.38

24.25

1.    The Measured and Indicated mineral resource was converted to mineral reserves based on $3.00/lb copper and $1,250/oz gold prices, 84% recovery for copper and 65% gold recovery within the ultimate pit design above an economic NSR cut-off of $7.45/t.  The resources are factored by planned mining dilution and ore losses to define the reserves. 
2.    Above a NSR cut-off of $7.45 / tonne and inside the designed ultimate pit.
3.    Includes 1,745k tonnes of additional low grade material as dilution.
4.    Numbers may not add due to rounding.

Although the Company believes the oxide and magnetite asset has potential economic value, it is not included in the reserve calculations.



Serrote Mineral Resources

Serrote Deposit Mineral Resource for Sulphide Material as of September 14, 2010

Classification

Tonnes (000)

Cu
(%)

Cu
(‘000 lbs)

Au
(g/t)

Au
(‘000 oz)

Measured

63,319

0.51

718,771

0.11

220.5

Indicated

55,894

0.48

596,779

0.08

150.1

Total Measured and
Indicated Resources

119,213

0.50

1,315,550

0.10

370.6

Inferred

5,024

0.35

38,633

0.06

9.2

1.    Based on 0.12% CU Cut-off.
2.    Numbers may not add due to rounding.
3.    Oxide material and the magnetite from the sulphide material

Although the Company believes the oxide and magnetite asset has potential economic value, it is not included in the resource calculations. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability.



Caboclo-Rogerio and Caboclo-Zeze Deposits

A detailed description of the resources for the satellite deposits is included in the Feasibility Study. The Caboclo-Rogerio satellite deposit includes a Measured and Indicated Mineral Resource of 10,056 kt sulphide material with 0.50% Cu grade, and 857 kt oxide material with 0.56% Cu grade, based on a 0.15% Cu cut-off grade. Minerals Resources that are not Mineral Reserves do not have demonstrated economic viability.