Encaustic is a wax paint that has been fused with high heat, onto a rigid support. It is very durable - impervious to light and moisture. There are encaustic paintings thousands of years old that are as good as new. I usually use a layering technique for my encaustic paintings, carving the top layer to reveal the underlying layers. Sometimes I embed beads, buttons, feathers, and pieces of paper, cardboard, or plastic into my encaustic pieces. To keep your painting looking good, just buff the surface every now and then with a soft cotton cloth. As with any other work of art, be sure not to put it in direct sunlight and don't scratch the surface by letting it touch anything.