Pre-World War Two, there were several plastics, Parkesine (1862), Xylonite (1869), Celluloid (1869), Galalith (1897 — aka Erinoid and French Bakelite), Bakelite (1909), Catalin (1927), and Lucite (1931 — aka Plexiglas or Perspex)
========================================================
Bakelite is quite heavy, but it has no grain.