TR-1: NOTIFICATION OF MAJOR INTEREST IN SHARES

For filings with the FCA include the annex

For filings with issuer exclude the annex

TR-1: NOTIFICATION OF MAJOR INTEREST IN SHARES

1. Identity of the issuer or the underlying issuerof existing shares to which voting rights areattached:

Petra Diamonds Limited

2 Reason for the notification (please tick the appropriate box or boxes):

An acquisition or disposal of voting rights

X

An acquisition or disposal of qualifying financial instruments which may result in the acquisition of shares already issued to which voting rights are attached

An acquisition or disposal of instruments with similar economic effect to qualifying financial instruments

An event changing the breakdown of voting rights

Other (please specify):

3. Full name of person(s) subject to thenotification obligation:

T. Rowe Price Associates, Inc.

4. Full name of shareholder(s)  (if different from 3.):

JP Morgan Chase

State Street Bank & Trust

Northern Trust Co.

Bank of New York Mellon Bank, N.A.

5. Date of the transaction and date onwhich the threshold is crossed orreached:

05 May 2015

6. Date on which issuer notified:

07 May 2015

7. Threshold(s) that is/are crossed orreached:

11%

8. Notified details:

A: Voting rights attached to shares

Class/type ofshares

if possible usingthe ISIN CODE

Situation previousto the triggeringtransaction

Resulting situation after the triggering transaction

NumberofShares

NumberofVotingRights

Numberof shares

Number of votingrights

% of voting rights

Direct

Direct

Indirect

Direct

Indirect

BMG702781094

57,347,249

56,438,826

57,736,817

56,805,760

11.02%

B: Qualifying Financial Instruments

Resulting situation after the triggering transaction

Type of financialinstrument

Expirationdate

Exercise/Conversion Period

Number of votingrights that may beacquired if theinstrument isexercised/ converted.

% of votingrights

C: Financial Instruments with similar economic effect to Qualifying Financial Instruments

Resulting situation after the triggering transaction

Type of financialinstrument

Exercise price

Expiration date

Exercise/Conversion period

Number of voting rights instrument refers to

% of voting rights

Nominal

Delta

Total (A+B+C)

Number of voting rights

Percentage of voting rights

56,805,760

11.02%

9. Chain of controlled undertakings through which the voting rights and/or thefinancial instruments are effectively held, if applicable:

T. Rowe Price Associates, Inc. (TRPA) serves as investment adviser, with dispositive and voting authority, to various institutional clients that own shares of Petra Diamonds Ltd., including the T. Rowe Price New Era Fund, Inc., which owns 15,471,233 shares. Such shares are registered in the following name(s):

JP Morgan Chase - 6,681,759

State Street Bank & Trust Co. - 45,074,401

Northern Trust Co. - 974,800

Bank of New York Mellon Bank, N.A. - 4,074,800

Proxy Voting:

10. Name of the proxy holder:

11. Number of voting rights proxy holder will ceaseto hold:

12. Date on which proxy holder will cease to holdvoting rights:

13. Additional information:

14. Contact name:

Gary Greb, Assistant Vice President

T. Rowe Price Associates, Inc

15. Contact telephone number:

001 410 345 2527