Gear is going to crystallize anyway when it's water-based. Your body will quickly absorb the water in the inj, then more slowly absord the gear, the gear usually forms little crystals. That's why water-based usually hurts so much, unless it's very finely micronized and doesn't form larger crystals. I've mixed oil and water a few times, never had a problem. Granted, they don't actually MIX, but I shake them enough so that they're somewhat homogenous before injection.