Since I have an 'in' in the tile business, I had Duane cut some larger pieces of limestone into 4x4 square which work out nicely to be a coaster. You can also purchase the tiles from Lowe's or Home Depot, just make sure you use the unglazed version, otherwise the ink won't stay.
I used Craft Ink which doesn't dry as fast, and works better on surfaces other than paper. Once I stamped the image, I coated them with a layer of clear embossing powder. Tap off the excess powder and then pop in the oven. Yep - you read right, the oven. Bake them at 350 degrees for approximately 10 minutes, or until all of the inked images appear shiny and embosseed.
Take them out of the oven, and allow to cool. Then I put a layer of cork on the back so that the coaster doesn't scratch the surface of whatever it happens to be sitting on. This cork I found at Hobby Lobby, and came in a large roll. I cut it to 3.5x3.5 so that they fit nicely on the back of the coaster.
Tie them all together with a pretty ribbon and you have a great home-made gift that is already packaged! I was really happy with the way they turned out, and was able to use my Stampin' Up! stuff in a 3-d practical way!
Let me know if you would be interested in doing a tile coaster class. Even without the monogram, they would make a great gift, and something that you could just have on hand if you needed a 'quick' gift for something!
Stamp Set: Friendship Blooms (Retired)
Ink: CRAFT: Old Olive, Ruby Red, Chocolate Chip, Creamy Carmel
Other: Limestone Tiles