Fibre Blanket is made out of the same material as other fibre products like paper and board. It is very similar in appearance to household insulation. It is made out of ceramic fibers with alumina, silica and organic binders in it, and it is woven together. It can be cut with scissors(but will dull them quickly), an X-Acto knife, or torn by hand to give a ragged edge. One side is usually smoother than the other. It typically comes in a 20" by 24" piece, or a 24" by 25 foot roll.
You can fuse directly on it for maximum texture. You can drape it over a mold and slump over it for a rough shape, instead of the more precise shape a clay or stainless steel mold will give you. You can cut out a hole in it and make a crude drop out ring. It can be used as insulation in a kiln or glory hole. It is an ideal base for fusing glass tiles on, as it will give a strong texture to the bottom which will help in sticking the glass tile to the wall or countertop.
If you plan to use the shape of your fiber blanket more than once, you should soak it with Ridigizer. Soak it in a shallow cookie sheet. Let the blanket become saturated in the cookie sheet. Once it is fully saturated, use a rolling pin or pipe to squeeze out the excess Ridigizer. You can save and re-use the excess Ridigizer. Wear gloves when using Ridigizer. Two pieces of fiber blanket cannot be stuck together with the Ridigizer. Spray your original piece with a separator agent like Pam. Mold the saturated piece of fiber blanket to the mold. Let it air dry. Some instructions say you can kiln fire it to make it dry quicker, but the Ridigizer has a flash point of a few hundred degrees C, which means Fire! Once dry, it should be coated with kiln wash. After that you can slump over it a number of times and always getting a constant shape. The mold will be very fragile so handle it with extreme caution. You can buy the fibre blanket already moistened, but it is very expensive that way. Do not let Ridigizer freeze or it loses its effectiveness.
It comes in 2 thicknesses, 0.5 inch and 1 inch. It will lose some thickness with repeated firings, roughly compressing in half. You can thin it down by pulling it apart gently.
Fibre Blanket should be pre-fired before use to burn off the organic binders. It gives off a mildly unpleasant smell, so make sure your studio is well vented. The binder will make the fiber blanket dark when it is burning off, but the blanket will return to a white colour once it is gone. You should fire to just beyond the temperature at you will be working at. Wear a mask, an apron and gloves once you have fired the blanket. The fibers can be unpleasant if inhaled.