An easy fix for this problem is the use of oxalic acid crystals for smaller rocks, or a poultice made of powdered clay and liquid rust remover. All of these products can be purchased at your local hardware or home improvement store.
Fill a large bucket with one gallon of distilled water and add one pound of oxalic acid crystals. Allow the rocks to soak in this acidic solution until the rust is gone. Slowly add baking soda to the oxalic acid mixture to neutralize it and pour down a drain for disposal. Rinse the rocks with a garden hose.
Use a thick paste made of powdered clay and liquid rust remover for larger rocks. Apply a thick layer of paste to the stains, cover with plastic wrap, and allow to sit for up to 48 hours. Remove the wrapping and scrape away the paste. Rinse the rocks with a garden hose.
Remember to wear safety equipment such as plastic gloves and goggles, and keep these materials away from children and animals.
Parsons Rocks is your Las Vegas source for decorative landscape rock. Call today at (702) 566-7625.