A few years back I got into stone picks. I love the tone for electric. (agate)
jazz III shapes 1mm to 3mm (no flex in either) although 3mm feels weird tip is too round top to bottom.
at first I just bought some. but liked them so much I ground some of my own.
I’ve made picks of several materials (each with a distinct tonal contribution)
Wood, brass, turtleshell, abalone, bone, hoof, antler, micarta, glass, coins, etc.
Lot’s of comparison. here’s what I liked:
Agate stone for electric. zero wear. easy on strings. no flex. no clicky plastic sound.
cons: expensive if you lose it. can break if you drop it on hard surface.
Deer Antler for acoustic guitar. best tone. warm loud. holds a good edge, gets grippy if you sweat
if you like i’ll up some pics of my pics.