The search turns up a page about a uranium seizure... red mercury is conjuctured to be used in fuses for the Suitcase Nukes that the Russian KGB made!
quoting:Thomas Nilsen 1997-09-21 12:00
3.8 kilograms stolen uranium seized in Caucasus
Russian police seized 3.8 kilograms of stolen uranium in the home of a man in the North Caucasus town of Ivanov on Thursday. The uranium has been traced to originate at the nuclear research center of Sarov (Arzamas-16).
The police seized the stolen uranium after they detained a gang suspected of trying to sell the highly radioactive substance, according to Interfax news agency. Several times the gang had tried to offer the uranium to prospective buyers in Moscow, the Baltic states and elsewhere. The uranium-238 was kept in a metal cylinder inside a lead isolator. Uranium-238 can be used to produce nuclear bombs by scientists with the bomb-developing know-how.
The police investigators also seized two jars containing highly toxic red mercury-oxide weighing about 2 kilograms. Red mercury is also belived to be a substance for developing small nuclear devices, like those suitcase-sized nuclear bombs former Russian security advisor Alexandr Lebed a week ago claimed that Moscow had lost the track of.
The police says to Interfax that the uranium comes from the federal nuclear research center in Sarov (former Arzamas-16), from where a container went missing in 1994. On september 16th, employees and scientists of the center startet protest actions because of the state's salary-debt to the center. They claimed that the center is in a catastrophic position and its safety jeopardized, because of poor financing.
U-238 can be gradually enriched into plutonium in a special "breeder" reactor, absorbing particles emitting by a running reactor (actually, a tiny portion absorbs neutrons and then undergoes beta decay, emitting electrons and turning into plutonium - left running long enough this builds up and can be extracted from the remaining U-238 around it). But in itself it is not useful for bombs.
When the article says "weapons grade uranium", that means a sample of uranium that is around 90% U-235, seperated out of a much larger amount of uranium ore. The seperation process is quite difficult, and is the step the Iraqi's have not managed to solve on a large scale themselves. So U-238 getting to Iraq, while obviously not helpful, doesn't get them a bomb or solve the problem holding them up. Enough U-235 of high enough purity does. Or plutonium.
I hope that helps.