Help Identifying Rocks
When they were building our house last year there were a lot of rocks in our yard. If it matters I'm in Columbus, OH. Here are a few that I saved and I've been considering using in my aquarium. I've given them a good scrubbing and I soaked them in hot water & a little bleach overnight. Vinegar did not fizz or bubble on any of the rocks. That's all I've done (besides rinsing them after the soak). The 4 bigger rocks appear to be the same type and the darker 5th one I'm assuming is slate. Any rock experts on here that can identify these rocks and whether they are aquarium safe?