How do I prepare a poultice & use it to remove stains?
A. Here is how you do it:
First, understand what a poultice is. It is simply a chemical or cleaning solution to break down the stain and an absorbent material to draw it out.
WEAR RUBBER GLOVES ALL THE TIME, WHILE HANDLING CHEMICALS!
- Mix it – using a metal spatula or spoon – in a glass or stainless steel bowl, together with the chemical, to form a paste just a tad thinner than peanut butter (thin enough, but not running.) Now you have made your poultice. If you’re attempting to remove a metal (rust) stain, first you melt the "Iron-out" with water – according with the directions written on the container – and then you mix it with an equal amount of talc powder, adding water if it turns out to be too thick, or talc if it’s too "runny".
Apply the poultice onto the stain, going approximately ½" over it all around, keeping it as thick as possible (at least ¼".)
Cover the poultice with plastic wrap, and tape it down using masking tape.
Leave the whole thing alone for at least 24 hours, and then remove the plastic wrap.
Allow the poultice to dry thoroughly! It may take from a couple of hours to a couple of days or better, depending on the chemical. Do NOT peek! This is the phase during which the absorbing agent is re-absorbing the chemical that was forced into the stone, together (hopefully!) with the staining agent, and you do NOT want to interrupt that process!
Once the poultice is completely dry, scrape it off the surface of the stone with a plastic spatula, clean the area with a little squirt of stone safe spray cleaner, then wipe it dry with a clean rag or a sheet of paper-towel. If the stain is gone, your mission is over! If some of it is still there, repeat the whole procedure (especially in the case of oily stains, it may take up to 4 or 5 attempts!). If it didn’t move at all, either you made a mistake while evaluating the nature of the stain (and consequently used the wrong chemical), or the stain is too old and will not come out, or it was not a stain, but it was a "discoloration" instead.
If you decide to use paper-towel instead of talc powder, make a "pillow" with it (8 or 10 fold thick) a little wider than the stain, soak it with the chemical to a point that’s wet through but not dripping. Apply it on the stain and tap it with your gloved fingertips to insure full contact with the surface of the stone. Then you take it from the point 3 above.