AshleyNicole said:My grandma's dirt road was all limestone and flint. Limestone includes several types of rocks found in florida including flint which is smoother. you can see fossils, seashells, etc on some rocks and some are smoother. You can see the pics in my gallery.
and yes i know there is calcium carbonate in limestone.. that was a mistype, but its not all calcium carbonate. There are different forms of limestone you know.
Codefox said:They're primarily found together...but they're still not the same thing. They're both sedementary rocks so contain many materials. But the fact that limestone is primarily calcite and that flint is silica is what seperates teh the two.
Flint isn't part of limestone. It just forms in it. (Primarily...flint can form in the absense of limestone.)
It may not seem important but it is very important to differentiate them when putting rocks in the tank. Flint is fine. It won't dissolve in your tank. Limestone will. Which is fine for fish that need a higher pH like cichlids.