@elliottbnewcombjr Gem Stones used as a Ball is a common replacement over a Steel Ball, has approx’ 25 Years behind it as a Concept, it was one selected for Idler Drives during the 90’s.
This was a ’biggy’ from about 2010 onwards when Lenco Idler Drives become a DIY Service Trend. The use of alternative materials, to be used as a Bearing Housing Ball was seen spoken about much more publicly since this period.
Gem Stones, as said are attractive, but also are Fragile and a Platter Spindle that can have a free movement vertically can take a Gem Stone out if a impact occurs. The same is for a Gem Thrust Pad. The idea of a Low Coefficient of Friction at the Spindle Base / Thrust Pad Interface from the use of a Gem is attractive, but there is risks present, that can easily be avoided, by selecting an alternative material.
I would have one myself, but the idea of giving the inherent risks over to another who might not fully understand the overall risk would not settle with myself.