Fibrous structure

A composite structure consisting essentially of a plurality of interlayered inorganic fiber mats and organic fiber webs held together over the greater part of their areas by needled fibers from at least one of the said webs, said needled fibers extending at least part way through one or more of the mats in the thickness direction thereof, sufficient to hold the composite together, said inorganic fibers being staple polycrystalline alumina or zirconia fibers having an average diameter of 0.5 to 5 microns, and said structure having a punch density of 60 to 260 per square inch.