a problem with sterling silver polish

what I do is ,start with silicone polisher white(coarse)and
black(medium) then blue(fine),sometime skip blue,then tripoli and
rouge.
At the end,I still get dark spot(i do'nt know what's call) after rouge
but surface is all smooth, when i try to get miller shine.
I 'm having this problem long time,especially sterling silver from
casting and larger surface(not casting).
I also tried bobbing compound before white sillicone. but not so great.
I need miller shine on sterling silver.


I 'd be appreciate if anybody give me good tip or nice example or any
careful point or How often should i change wheel of tripoli and rouge,
etc.

thanks in advance.
zz212

wrote:

At the end,I still get dark spot(i do'nt know what's call) after rouge
but surface is all smooth, when i try to get miller shine.
I 'm having this problem long time,especially sterling silver from
casting and larger surface(not casting).

I am not sure what you are describing but I assume the problem may be
fire scale (stain).

Please read further Lewton-Brain's article on FIRE SCALE at

http://www.ganoksin.com/borisat/nenam/firescal.htm

Ganoksin site may also have instructions polishing - though I
haven't had time to check.

best of luck
norwick