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I'm interested in that, but I only have a few mins. Can you give me at most the first 500 characters of a detailed explanation in English about that?
If you are specifically looking for a river rock, the best place to look is a river bed. You can find rocks that have similar qualities at creeks, lakes, and on beaches. You can choose any rock that appeals to you, but rocks that are smooth are ideal for painting. Weathered rocks that that have been in the water for a long time are great for painting because they have tumbled, which has left them smooth and rounded.  You can’t take rocks from state and national parks. Be careful when you are sea