Gerald Lange wrote:
> If so, has anyone ever suggested an even bigger step, but perhaps not
> an unnatural bump forward - that this was made in a sandwich mould?
> This would only require secondary "casting." This guess made on other
> measurements and certain moulding characteristics (stretch and
> planing) that seemingly are in evidence here.

Sorry, my readings about the Disk are very old, and my memories are emerging

I just recalled two more arguments against the molding of the whole disk:

1) One face is slightly more flat that the other; on the flat face, the
signs are less deeply stamped, and some of them are slightly stretched.
This seems to suggest that, after making the first face, the disk was turned
face down to stamp the second "page". The face laying on the table would
then have been compressed by the weight of the clay and by the pressure
exercised on the other side. If the disk just had to be an master copy to
build a mould, there would have been no reason to use both sides of the
clay: each face would have been stamped on separate pieces of clay.

2) The edge of the disk is rounded. This is what you expect when a ball of
clay is manually flattened on the table. On the other hand, if you press
clay between two sandwich moulds, clay squeezes out from the sides; the
natural thing to do is to get a knife and remove the excess clay before
opening the moulds: in this case, the edge should be a cylindrical surface,
like the edge of a coin. If the excess clay was not trimmed off, then we
should see the border of the mould on the two faces.

_ Marco