Here are two excerpts from the article that may pertain to what you are asking about.
“The outer shell of the great pyramids was covered with white tufa limestone, a good electrical insulator.”
“The blocks inside the pyramid were cut from a different limestone quarry. These blocks contain crystal and small amounts of metal, and have electrically conductive properties.”
Just keep in mind that the Giza pyramid was a multipurpose device. Depending on the purpose you have in mind a thin frame may work. The stronger energetically the material is that you use for the frame, the stronger the energy inside the pyramid will be, and the effects on the outside of the pyramid.
I have heard of an interesting experiment where someone is only using laser light to create the frame of a pyramid.
If you are interested in experimenting with that, the cheapest lasers that I have found are at a pet store in the cat toy aisle.