If there is any color transfer or any doubt about the appropriateness of the use of interleaving, a mat with outer wrapper or cover should be used. Glassine is not a very stable material and should be replaced when yellowed or extensively creased. These tissues vary in their translucence. Some of the more heavily buffered tissues can be inherently abrasive, and many of these tissues crumple and crease easily, also creating an abrasive surface. Because it is heavy, it can be space inefficient, but the heaviness is also advantageous in that it is difficult to crease and crumple.
Bond paper is less common, but it is appropriate interleaving material to use in some cases.
Clear polyester film, commonly known under the DuPont trademark as Mylar, is very stable and long-lived and can be used as an overlay sheet for works on paper stored in mats or folders. Uncoated, Mylar D is recommended because it is most stable. Also avoid the frosted variety because it is strongly abrasive. The exceptions to its use would be any object with a friable design such as charcoal or pastel. The static cling of the polyester films will pick up such design materials.