I have about 50 EDDs, given to me by my wife’s aunt. I have a similar number of newer 78s, including a couple of real “albums” from when that term made sense. Several records in individual sleeves, bound together in a book.Bakelite? You have Edison Diamond Discs? I have a few.
Most 78 (and pre-78s) are made of shellac.
78 rpm was a NAB compromise of Victor 76 and Columbia 80 for a uniform speed standard the broadcasters wanted. They were sick of having to adjust speed for each record. Early records varied by company from 70 rpm to 120 rpm.
Some of the EDDs have embossed labels, some have paper, and there are, sadly, a few with missing paper labels. If I ever get breathing time (still revamping my wife’s den and a full bathroom, not to mention yardwork, etc., etc., etc) I’ll look them up on discogs from the embossed numbers.