What Sort Of Rock Is This?

[Karl1987]

Ive got 3 rocks for my planted tank and wanted to know what sort they are and if there okay to use just incase they will raise the ph.

 

[garuf]

Ive got 3 rocks for my planted tank and wanted to know what sort they are and if there okay to use just incase they will raise the ph.

look an awful lot like granite and quartz to me, should affect your ph at all