Gold prices have moved sideways this week and gold on the December contract has gained just 0.3% to $1,720 over the last five trading days.

Of course, the only practical way for most private investors to invest in gold is through exchange-traded funds. The performance of the $63 billion SPDR Gold Trust ETF (NYSE: GLD) has crept ahead of its underlying commodity this week, gaining 0.66% to $166.73. The London-listed Gold Bullion ETF (LSE: GBS.L) moved the other way and was down by 0.5% to $166.02 on the week, in Thursday afternoon trading. Both funds are up around 9% so far this year.

Gold's big movers
Many investors prefer to invest in gold mining stocks, rather than gold itself, as investing in miners offers the potential for leveraged gains on the price of gold. Let's take a look at some of this week's biggest movers.

Shares in Egyptian gold miner Centamin (LSE: CEY.L) have risen strongly this year as the company looked like it was finally delivering promised production gains and growing profits. However, the company's stock plunged by almost 50% earlier this week before being suspended, following an Egyptian court decision that appeared to revoke the mining concession agreement for Centamin's Sukari mine. The company has since lodged an objection that has delayed the implementation of this ruling while they investigate further and launch a legal challenge. Trading in Centamin shares resumed today and the shares shot up by 13% to 72 pence, suggesting that some bold (or well-informed) investors believe that the company's prospects in Egypt may not be as bleak as they first seemed.

Rambler Metals (LSE: RMM.L) climbed 9.5% to 38.4 pence this week as its Ming copper-gold mine in Canada formally entered commercial production, following a period of 60 days during which it operated at 85% of production capacity. The company's share price has risen by 45% over the last three months as it moved steadily toward this stage, crowning a successful year for the company. Rambler CEO George Ogilvie said the company would now focus on using growing free cash flow to pay down debt, which he said was "of paramount importance."

Eldorado Gold (NYSE: EGO) has gained 6.4% to $14.86 so far this week, despite unveiling a 26% fall in profits attributable to shareholder for the past quarter last Friday. The company says it remains on target to sell 660,000 ounces of gold this year. Eldorado's cash operating cost of $465 per gold ounce is attractively low, meaning that profit potential is strong. The company is also in the early stages of bringing a new gold mine in Turkey into production.

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