Dr. Fred Hueston has invented the Stain Sponge, combining the necessary stone-safe surfactants and diatomaceous earths with the ease of a bag similar to those used in teabags, and invented the first easy-to-use poultice stain remover for stone products.

The bag is soaked in water and placed on the dampened stain, then covered with a piece of plastic wrap. A few holes are punched in the wrap to allow for slow drying of the bag. As the bag dries, the stain is drawn into the poultice inside the bag. After 12 to 24 hours, the bag should be dry, and is removed.