Hello , 
        I'm presently doing the work of glass beads and my question is
about making transparent beads opaque of the same color of which the
bead is . For that I'm in need of the enamel or any other coating
which can make that beads opaque and have to be of permanent finish .
        For example if I have red trnasparent beads with than I wish
to make that same bead opaque .

How about tumbling the beads in an abrasive that will scuff the
surface and make them opaque.

If they are glass beads, you can etch them.  Same thing is done with
those neat frosted glasses with some design on them -- they're
manufactured the same way.

Both tumbling and etching, mentioned above, can make transparent glass
"frosted" or translucent (meaning that some light passes through it),
but it's not easy to make it opaque (meaning that no light passes
through it).

Here's a product that will give a frosted, translucent look to glass items:

http://www.rustoleum.com/Product.asp?ddf=10&frm_product_id=38&SBL=1