Various Issues With Slate!

Please do a quick review of all these issues. If one applies to your situation, you will be very happy that you did.

Dark Brown and Black Slates

There are some dark brown and black slates that have an unusually high oil content. These slates may show light areas from routine cleaning when the cleaning process is removing some of the oil that creates the dark color. Sealing will prevent this from happening.

Color can be restored by applying Aldon "Efflorescence Treatment", if the slate can absorb it.

A high oil content slate should only be sealed with a solvent based sealer like Aldon S-B-S Sealer.

Do not use any companies water base sealer as the risk of problems is too high. "Oil and Water Do Not Mix" is true.

One way to find out if this is true of your slate is to saturate a small section of one piece with lacquer thinner , press down with a CLEAN, WHITE cloth. Now, see if the liquid being absorbed into the cloth has a darkened appearance and the slate has a lighter color than the untreated area. If the color is now different, it can mean high oil content.

If your slate has a high oil content, overuse of a solvent sealer, including S-B-S, could dilute and float the oil leaving an uneven color. Therefore, follow the S-B-S label to achieve a good sealing job, but go slow and watch for any color blotchiness from the oil.