Science Forums 2

[Eclogite]

A few random thoughts on your speculations:

1. Sarcophagi are not especially large when compared with some of the stones used in portions of some temples and pyramids.

2. You mention grey granite is harder than sand. Not so. Granite consists of mainly quartz, feldspar and mica. Most sand - and certainly the sand you would use for grinding an polishing, consists of quartz. Feldspar and mica are both softer than quartz. Therefore we can certainly grind and polish a block of granite with sand, especially if we have a lot of sand. (What would be need as a source for sand? Let's see - a desert might be quite useful.)

3. You mention the possibility that the Egyptians built their monuments around pre-existing granites blocks. I don't see how that would work for the Great Pyramid, where the Grand Gallery, rising high in the pyramid towards the King's chamber, with both lined with granite yet surrounded by limestone blocks. (In passing, my recollection - having stood inside the Great Pyramid many times - is that the granite here is red.)