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Posted by: Donald Kasper
When the Russians formed banded silica structures in platinum vessels in supercritical fluids in a few months using quartz sand, I wrote and asked if they could use bentonite instead. They laughed at me. I mean, why use silica with 800 grams per square meter surface area when they are perfectly happy using sand with 1 gram per square meter. Because surface area relates to reaction rate. This is why massive quartz and sand cannot make agate. The reaction chemistry is colloidal and in a colloid world it is all about chemical charge, surface area, concentration,and temperature.