The Saudi Arabians, who for a half-century have accrued fabulous wealth from the world's largest deposits of "black gold," are now prospecting for real gold at a site some say was one of King Solomon's mines.

The gold deposits, mined periodically since ancient times, run in a crescent-shaped seam near Mahd adh-Dhahab, a small town northeast of the Red Sea port of Jidda.One expert estimates current deposits at about one million ounces, worth nearly $500 million. That's a pittance compared with what the country has earned from its oil, about one-quarter of the world's known reserves, which transformed one of the world's poorest countries into one of the richest.

The Mahd adh-Dhahab isn't expected to trigger a California-style gold rush, but it will help the Saudis in their drive to diversify their economy.

Mining in Saudi Arabia spread throughout the western part of the kingdom between the 8th and 13th centuries before mysteriously dying out.

It was revived in the 1930s, when oil exploration brought geologists to Saudi Arabia. King Abdul-Aziz, founder of the modern kingdom, instructed one of them, an American named K.S. Twitchell, to explore the possibility of a modern mining industry.

Mahd adh-Dhahab was reopened, and between 1939 and 1954 some 750,000 ounces of gold and one million ounces of silver were mined there. It was closed in 1954 because it was losing its profitability.

Mahd adh-Dhahab's most recent revival was in 1984, when the state-owned General Petroleum and Mining Organization, Petromin, was asked to develop the site.

The prospect of mining profits has attracted foreign investors. But exploration licenses and mining leases are difficult and time-consuming to obtain. This is partially because the government is trying to develop formulas for the capital investment and revenue sharing between the public and private sectors.

"There's been quite a lot of interest here," one source says. "But most people are put off by the delays."

A U.S.-based, Australian-owned company called Utah International-BHP, along with a Saudi partner, has applied for an exploration license to prospect at al-Amar, east of Mahd adh-Dhahab.

There also is interest in Canada, which is submitting a proposal for government-to-government cooperation.

"We're very enthusiastic with the mineral content that we know of," one Canadian official told The Associated Press. "The Canadian private sector and the Saudi private sector are ready to go. They just want to know the terms and conditions."

No one is likely to get rich quick. Mining requires huge amounts of capital. Experts say that only one percent of all exploration projects result in economically worthwhile mines and those take two to five years to become fully operational.