Among them are fireproof paints, grinders and bearings.

As they are highly adherent, the paints are very useful in casting.

The corundum grinder, low in production cost, is as strong as diamond grinder, and long in the serviceable life.

The corundum bearing can be used without supply of lubricant. The bearing has already proved effective in operating various kinds of machines.

Corundum can be also applied to jewel cutting.

The corundum-made products won patent right and certificate at the 12th National Exhibition of Inventions and New Technologies last year.

The Democratic People's Republic of Korea is abundant with corundum resources.