LONDON -- Gold on the February contract has weakened slightly this week and has fallen 1.2% to $1,670 since last Friday.

Of course, the only practical way for most private investors to invest in gold is through exchange-traded funds. The largest gold ETF, the $72 billion SPDR Gold Trust (GLD -0.19%), has fallen 0.8% to $162.15 since last Friday's open, while London-listed Gold Bullion Securities (LSE: GBS) has slipped 0.9% to $161.36 over the same period. So far this year, shareholders of Gold Bullion Securities have seen their holdings rise by 0.6%, while SPDR Gold Trust holders have gained 0.1%.

Gold's big movers
Many investors prefer to invest in gold-mining stocks, rather than gold itself, as gold miners are able to use their operational gearing to outperform the price of gold. Let's take a look at some gold stocks that have gained strongly recently.

Randgold Resources (LSE: RRS) has climbed 4.2% to 6,145 pence over the last five days, after the FTSE 100's biggest gold miner confirmed that production had returned to normal after a recent fire at its Tongon plant in Ivory Coast. Randgold's share price remains 20% lower than at the start of October, ahead of the publication of the company's Q4 results on Feb. 4.

HudBay Minerals (HBM 0.13%) has climbed 30% to $12.04 over the last three months. The Canadian gold and silver miner signed a $750 million financing deal with royalty company Silver Wheaton in 2012, which gave HudBay a $500 million upfront cash payment. In return for this, HudBay is committed to selling the gold and silver production from its 777 and Constancia mines to Silver Wheaton at artificially low prices until 2016 -- $400 per ounce for gold, and $5.90 per ounce for silver. Given HudBay's share price gains, investors seem to have welcomed this deal.

Trans-Siberian Gold (TSG) is up 15% to 47 pence so far this week, after the gold and silver miner provided a strong update on production at its Asacha mine in northeastern Russia. Trans-Siberian increased its production of refined gold and silver in every quarter of 2012 and year-end production totalled 27,588 ounces of gold and 35,110 ounces of silver. Trans-Siberian also recently recruited additional technical staff to supervise the ongoing development of the mine.

Shares vs. commodities
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