I don't know the density of Aegis, but there was a thread recently about ferrule hardness, which had many different types of ferrules listed. That info may he helpful to you.
By the way, Juma and Elforyn are different materials.
I had searched before I posted this new thread but didn't find anything. Juma and elforyn are not exactly the same, but they are - as far as I know - pretty similar and the elforyn is mainly optically different. As far as I know the density of both are the same. But I only wanted to give an example which value I'm interested in.
Couldn't find the thread but I did copy the Ferrule Hardness List.
I don't remember the original posters name,
but this info was compiled with the help of many AZ'ers who sent
pieces of various ferrule material to be tested.