Gold crossed the important $1,000 an ounce barrier again Tuesday for the first time in six months.

Spot gold has risen above $1,000 just five times -- on Tuesday, in February and three times in March 2008, when it hit a record $1,030.80, CNN reported.

Analysts say the weak dollar is one important reason gold prices have been climbing higher. They say it's a good hedge against out-of-control government spending.

"Gold's rising price is due to uncertainty all the way from personal investors right through to institutions," said Sandra Close, an analyst for gold research group Surbiton Associates.

"There are questions out there over the health of economies, where interest rates are going. All that encourages gold hoarding. There's potential to see the price go even higher."

Many expect gold to go higher, possibly over $1,200, but say it could be difficult for gold to stay that high.

"I think these high levels could trigger selling ... and it might be difficult for gold to sustain the $1,000 level," said Shuji Sugata, a manager at Mitsubishi Corp Futures & Securities in Tokyo.