What material were the original outer casing stones of the Great Pyramid?

What material were the original outer casing stones of the Great Pyramid? They were white limestone quarried at Tura.

Tura limestone formed the Great Pyramid’s smooth, bright outer casing. Unlike the rougher local limestone used for much of the core, these blocks were carefully dressed and fitted to create polished, sloping faces. In sunlight, the finished pyramid would have appeared far more reflective and sharply defined than the weathered stepped surface visible today.

The Tura quarries were located on the eastern side of the Nile, roughly 10 kilometres southeast of the Giza Plateau. Workers transported the stone by boat, probably using the river and connected waterways before hauling it onto the construction site. The 2013 discovery of the Wadi el-Jarf papyri, including the diary of an inspector named Merer, provided a contemporary record of limestone deliveries from Tura to Giza.

Most casing stones were removed over many centuries, especially for later construction in Cairo, and earthquakes also contributed to losses. A few original casing blocks remain near the pyramid’s base. Granite was used inside important chambers, but it was not the material of the original outer casing.