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Why do I have Brown Spots on my Granite and how do I remove them?
QUESTION
I recently had granite installed and after a few days, I noticed these brown spots appearing in a few spots. I tried using several cleaners and nothing is working and am trying to find something to remove it. The installer said that because it's a natural stone, it may have oxidized and out of his control. I'm not sure why it would do that but tried that Rust Ex and it didn't do anything and found my way to your site and figured to ask. Any insight and guidance is very much appreciated.ANSWER
ANSWER - Determining what is causing a stain or how to remove it, depends on whether this is a granite countertop or a granite floor tile or a granite wall tile in a shower or what... Also is it inside or outside and what are the climatic conditions, and what are the underlying conditions of where the stone is installed. Also depending on whether the stone has a polished or honed or flamed surface can make a difference.Natural stone consists of a blend of different minerals and often contain iron oxides that when subjected to moisture can cause a rust stain. Sometimes a metal object touching the stone can cause a rust stain. Surface rust stains are generally easier to remove, but if they are deep stains they can be hard or impossible to remove completely. I would try one of the stain removers sold by stone suppliers to see if it will work. Always be careful and test what you do before going to far with it or you could have bigger problems. You can consider hiring a professional stone restoration company to have them try to remove the stain.
If you seal the surface of the stone with a stone penetrating sealer it can help keep surface moisture away.
2 thoughts on “Why do I have Brown Spots on my Granite and how do I remove them?”
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A brown stain appears on the top surface of granite grouting joint newly completed & not occupied for 7 months (Brand new). Installer cleaned it away. Gradually the brown stain spread along the joint reaching the bottom of vertical grouting joint. Visually, the interfacing gap of 2 slabs of granite has no seal applied to it. Eventually, below this brown stain vertical grouting line, the top surface of cupboard is damaged by brown colour liquid. On 2 occasions, contractor just clean away the stain without reinforcing the grouting joint.
I suspect the interfacing gap of granite slab without seal is trapped with water during cleaning using damp cloth. This accumulated trapped water eventually drip to the cupboard below & cause water damage after moving in for 8 months. Granite specialist claimed that water was allowed to flow beyond the edge of granite worktop but the rest of bottom cabinet & footing of cabinet is fine & floor is not damage. The cabinet & cupboard below the granite worktop is built sunken-in & how water got landed on top surface of cupboard? I wish I could attach pictures for reference.
What can cause this problem.
I’m not sure I fully understand your situation. Normally slabs of granite would have the joints filled with an epoxy and silicone or polyurethane sealant to make the joint water tight. Particularly if the joint is a transition joint like the inside joint between to adjacent walls.
If you have a cementitous joint then some grouts can bleed stains when they get wet. Or a contaminate can absorb into the grout joint and diffuse or migrate into the adjacent areas. Water is the carrier of stains. So if you can prevent water from migrating into the joint that might or might not fix the problem. Just depends on what is the problem.