Understanding Calcite Based Stones Such as Marble

Understanding Calcite Based Stones Such as Marble

There is currently no penetrating sealer that can stop etching on calcite based stones. On Absolute Black granite etching causes gray rings and spots on the surface. A topical sealer is not recommended for natural stone because it blocks the pores of the natural stone then can't breathe and the top coating can scratch easy. So what happens to natural stone that can't breathe? Moisture gets trapped and can cause a chemical and mineralogical change within the stone. This action of decay in natural stone may take form of pitting, spalling, flaking and oxidation. You want your natural stone to breathe or it will disintegrate.

The Granite Shield process on calcite based stones will not prevent surface etching but will reduce it about 80%. Granite Shield does have a repair kit that should etching happen if sealed with Granite Shield sealers remove etching in minutes on polished or honed surfaces. Acidic liquids, alcohol and vinegar can etch marble, travertine and limestone if left unattended on your stone surface. Water with a lower pH level lower than 7 is considered acidic.

pH Values

Stomach acid 1 to 3
Lime Juice - 1.8 to 2
Lemon Juice - 2.3
Coca Cola - 2.5
Soft Drinks - 2.5 to 3.0
Vinegar - 2.4 to 3.4
Apple Juice - 3
Orange Juice - 3.5
White wine - 3.0 to 3.3
Red wine - 3.3 to 3.5
Drinking alcohol such as gin, rum and vodka - 3 to 6 adding Orange or Lime juice will lower pH
Tomato & Tomato Juice - 4.2
Beer - 4.5
Coffee - 5.5
Normal rain - 5.7
Milk - 6.2
Saliva - 6.3 - 6.6
Dog urine - healthy is 6.2 to 6.5
Drinking water - 6.5 to 8
Water - Under 7 is considered acidic

For more information and products to maintain marble and calcite based stones