The skull was then readied for jacketing. Prior to doing that, a small woden frame was measured up and assembled with glue and small nails. This frame will be incorporated into the skulls plaster jacket later on and provide both strength and allow the jacket to sit flat on a table, not rock back and forth.
Before the skull was jacketed, several things needed to be done. Any deeper low spots (gaps between teeth mostly) were packed with wet toilet paper, then dry sheets of same were put on the skull and dabbed with a wet paintbrush. This toilet paper layering is done until the brown bone coloration can no longer be seen. The toilet paper acts as a separating layer between the skull and the plaster jacket. If you don’t create a separating layer, you are putting plaster directly on to the bone which will have catastrophic results- it will be hard to remove the set plaster without damaging the fossil.
There were still a couple areas on the skull that were rather deep (antorbital fenestra in particular) so these were carefully filled in with solid plaster of Paris until the depression was flush with the rest of the skull. The plaster is mixed in a rubber cup which is easy to clean when finished- you just squeeze the cup and all the dried plaster cracks and falls out.