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Find Out if Your Stone is Acid Sensitive

Simple test to see if your stone is acid resitant or acid sensitive.

Some natural stones are sensitive to acidic substances such as orange juice, mustard or vinegar. When these items come into contact with acid sensitive stone, it will etch the surface (leave a dull mark). Some homeowners don’t mind the etch markings and feel that they enhance the natural, unique character of stone.

Directions
1. Find an inconspicuous testing area on the stone surface or use a sample piece.
2. Spill a few droplets of lemon juice on to surface.
3. Let it sit for 1 minute and then blot juice with a white towel to remove from surface.
4. If you see a dull spot where the juice was applied, your stone is acid sensitive. If you don’t see a dull spot, your stone is acid resistant.
Note: Above instructions are for reference purposes only.

How to avoid or minimize etching?
• Consider using silicate stones where food spills are most common. Silicate stones are very hard, durable and generally acid resistant. Examples: granite, sandstone, slate and quartzite. This is why you see many homes with granite kitchen countertops.
• Use coasters under drinks and placemats or trivets under food.
• Consider using a topical sealer to prevent etching on acid sensitive surfaces. Please note that topical sealers alter the appearance of stone surfaces by providing a high gloss shine. Therefore, it is often used on exterior surfaces such as slate or flagstone.
• Immediately clean up spills to minimize etching.

How to remove etches?
Refinishing powders restore smooth surfaces by removing etch marks. The techniques employed require special training and equipment, and therefore should be done by a stone professional.