Please told us a little more.
It is pure Tungsten or a Tungsten carbide.
The diameter is 0.35 mm, it's length?
Qty to handle , or batch size.
Meanwhile you can try with the same grinding wheel used to sharp Tungsten carbide turning and milling inserts tools . Such wheel are made from Silicon Carbide , they are soft green color .
Other solution is Diamond or CBN abrasives , see at
or try here