Just to add a couple of personal insights to the topic of botryoidal
jade, discussed so well by Mr. Friesen:
In my opinion this material has high value for the usual reasons:
uniqueness and rarity. Production from the original discovery along
California’s Central Coast has always been very small. The upscale
boutiques in and around Cambria, CA (near the discovery site) often have
beautiful examples of this material crafted into one-of-a-kind jewelry
in high-karat gold. They sell at “upscale” prices, too.
As you all know, the word “botryoidal” means "like a bunch of grapes."
And some of the lighter green botryoidal jades, when skillfully
polished, have an uncanny resemblance to small bunches of green grapes.
I have not seen material from the other location mentioned by Mr.
Friesen but the coastal material is nephrite in the usual nephrite color
range from gray through many tones of green to near-black.