(Reuters) - "Crystallex International Corp. said that sharp increases in its stock price and trading volume followed a 'clear signal' that Venezuela is pushing forward on mining projects.

Junior miner Gold Reserve Inc. said earlier that it gained environmental approval and a construction permit for its Brisas gold project in Venezuela. Its stock jumped as much as 69 per cent after the announcement.

'The awarding of the Brisas environmental permit is a clear signal that Venezuela is fulfilling its promise to advance mining projects,' said Crystallex Chief Executive Gordon Thompson.

'Crystallex is in the final stages of environmental permitting for the Las Cristinas project and looks forward to the timely conclusion of the permitting process at (the Ministry of the Environment and Natural Resources).'

In 2002, the Toronto-based company won the contract to develop the Las Cristinas deposit, seen as one of the largest in the world, with an estimated 13.6 million ounces of gold in proven and probable resources.

Crystallex stock rose as much as 37 per cent Wednesday, before retreating somewhat later in the session.

The shares were up $1.13, or 32 per cent, at $4.65 on the Toronto Stock Exchange by late afternoon, making it the No. 3 percentage gainer. Nearly 1.5 million shares changed hands, a big spike from the 30-day average of 770,000 shares per day.

On Amex, the stock rose 33 per cent, or $1.01, to $4.06.

Crystallex stock rose 17.5 per cent in busy trading earlier this month on speculation that Polyus, Russia 's biggest gold miner, was looking to buy some or all of the firm. The company said at that time it was unaware of any corporate developments".