I too am contemplating entering some sort of international or national contest... Though, I will be representing Canada, eh?
As far as stones are concerned however, although most substrate more or less look the same and are easily attainable, as well as most pieces of driftwood or even plants, that is not the case when it comes to rocks. At least here in Toronto Canada.
The rocks that Amano uses have incredible micro-detail and are FAR FAR different from the Utah ice or granite slabs you find at your LFS. Sometimes you find nice petrified wood, or even that black rock with the whitish-grey veins, but it seems the kubu basa, wiki tiki, or akriro kirusawa stones are like a $100,000,00 per pound (number may be slightly exaggerated) and available only online shipped to you for a price exceeding e amount of the stone....
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