|MadSci Network: Earth Sciences|
In answer to your question -- Quite simply YES. Hydro agates do exist and I've seen some fine examples as do crystals with little bubbles therein. The water is not injected. I believe that the water will never (in a million years) form a complete hard centre. In processing such agates it is very important not to breech the bubble walls as the trapped water would escape. Then all your left with is an agate geode. Alec McCreadie
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