Prominent mining sector identity Robert Champion de Crespigny and three other directors of resource investment house Mineral Securities Ltd (Minsec) have resigned at the request of its friendly merger partner, copper miner CopperCo Ltd.
The other directors resigning after not being invited to join the new CopperCo board are Sir Bruce MacPhail, Nigel Hamway and Stephen Phipps.
"Their resignations have been tendered at the request of CopperCo Ltd, the controlling shareholder Minsec," Minsec said in a statement on Monday.
"John Moore AO and Keith Liddell remain directors of the company."
CopperCo, which holds 94.7 per cent of Minsec, is moving to compulsorily acquire its remaining shares.
After CopperCo holds all of Minsec's shares, Minsec securities will be de-listed from London's Alternative Investment Market (AIM) and the Australian stock exchange (ASX).
Minsec's 19.8 per cent stake in CopperCo will be disposed of within 12 months after completion of the merger by seeking the approval of shareholders in the enlarged entity to cancel or buy back those shares.
An alternative is the disposal of the shares through a rights issue or placement.
CopperCo and Minsec announced the all-scrip merger on January 29, which would create a diversified base and precious metals miner.
Following the merger, CopperCo shareholders will own about 54 per cent of the enlarged entity, and Minsec shareholders and option holders will hold about 46 per cent.
Shares in CopperCo were up 1.5 cents, or 5.36 per cent, at 29.5 cents at 1214 AEST while Minsec's shares were unchanged.