I have never work on what you are calling lava stone but I would recommend treating it like granite. First do an acid test to see if etches, if it does not etch then approach it as if it granite. do you have Pictures????
Pictures always helps to indentify the stone and how one might go about restoring it.
Does the stone have scratches , what the problem you were called into fix??
Need more information
John E. Freitag
The Stone and Tile School
Has anyone ever worked on lava stone countertops before
(what type of diamonds )?
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