this thread is uncanny
Last Thursday I was having a coffee with a Jeweler mate of mine and talking about a diamond front sight.He and I both did the gemmological course together years ago and are both qualified gemologists.As I am moving house I have been selling all my gem books,lab instruments and faceting machine and generally divesting my self of all my gemmo gear.
Diamonds ,I know about.
Any stone supplier can supply a clean white stone for this purpose,they are not expensive when they are that small they only get expensive when the wife statrs looking at them. Any stone setter or jeweler can set it for you.It aint rocket science.A four claw mount would let in more light than a rubbed setting .
good shooting

sbs470