Thoughts on Powerstones

[SRoach]

Quartz is a component of granite, so if Shape Earth can "Clarify" a flawed gem, how about using it to merge several, seed-sized crystals from a much larger chunk of rock?

What about lab grown crystals?

Either of these things could greatly suppress the price.

That said, my reading of the spell is that ANYTHING COULD be made into a Powerstone. A chunk of quartz, a Brilliant cut diamond the size of your fingernail, an autographed baseball from your Little League years, signed by all your teammates... Just, valuable stones items are EASIER, and thus more popular for enchanting.
Presumably, you could enchant the diamond of an engagement ring, for the first couple dozen points, then "over" enchant it, at a cost of 4x, for as high as you were willing to risk the previous enchantment steps, to have an especially compact Powerstone. This from page 69 of "Magic". Last paragraph on the page.
(Actually, considering the value of a diamond ring, you should be able to pump it up as high as you dare. (($10*(P^2))+($40*P)) means an ideal item to turn into a 10 point Powerstone would cost $1400, and a suitable item for a 20-point one would cost $4800. Both inside the average cost of an engagement ring in 2023, of $5,500. Of course, this assumes, probably erroneously, that the costs are modern costs.)

Frankly, the costs of Powerstones fails my gut-check, because the value of enchantment, per Energy Point, is only $33 (in a TL3 setting), so the inherent cost for a single casting, into gemstone, of the spell, would be $660, and $2640 for casting it into, say, a random rock you plucked out of the road or stream. Somewhere, there is a breakpoint where it's cheaper to over-enchant the same, maxed-out, gem than it is to buy a big enough intrinsically valuable item in the first place.