Friday, February 13, 2015

Chasing out more Skull Fragments and an unexpected Bonus

Since the last post we have been actively taking off the large blocks three pieces of what look like more skull fragments. Since they are still embedded we don't know how large they are, but we have hopes.

Two of the fragments are located on block 1, which we haven't done much work on. Almost all the work over the last two years have been on block 2. I've had to reduce the hour I spend actively scribing due to tendonitus. So I started by pulling out block 1 and removing the plaster. It is as big as block 2 and shares a common cleavage plane so it should be just as productive. Lo and Behold after cleaning we find two skull fragments showing on the surface. Jerry has been given the opportunity to dig them out. Here is a closeup of one of them. There appears to be some large holes in the bones right in the center of this picture. These may be semi-circular canals, though they are much too large to fit in the brain case bone where you'd expect them. We have another scrap with holes like this showing. It will be great to compare the two.

Here's an overview of the block 1 with the part shown above directly in the middle and another skull fragment above it (shown to the left as the picture is turned).

Here is a closeup of possible skull fragments on block 2 / block 1 cleavage plane. Some of this may be centrums, but part is definitely more skull fragments.

Here is block 2 after the end was knocked off to access the skull fragments better. To the right you can see a wonderful invertebrate shell. The sutures look like a nautiloid, but the overall shape is that of a spherical ammonite. We'll just have to see what is is after removal.
 Here is a closeup of the shell. It is really big - over 3 inches across - and will be complete! The lip of the opening is visible, so we have the entire shell.
 Last of all, I have made an archival cradle for the large left side skull roof fragment. I followed the same steps as making the full skull cradle. First, prepare an oversized plywood bottom to be the base.
 Next, wrap the bone in aluminum foil to keep it clan, and apply a layer of clay about 1/8 inch thick tomimic the future foam padding.

Then make up plaster re-enforced with chopped glass, and embed the bone clay-side down into the plaster. You have to work fast as the plaster sets in about 6-10 minutes!
 Last, after the plaster sets remove the clay and aluminum foil and add the padding. Good for a hundred years!

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