Three Carvings in Black Stone of Mayan King Goddess Chichen Itza Mexico Signed

Description

Three hand carvings in black stone from Mexico, signed by artist.  Unsure if the stone is obsidian or something else.  Thanks for looking!
The left 3 1/2" x 5 1/2" carving reads:
Pacal the Greatest King of Palenque
He ascended the throne at the age of 12 years and died at the age of 80 years.
By: E. Camal
The middle
3 3/8" x 5 1/2"
carving reads:
Young Ixchel
Mayan Goddess of Medecine
By: E. Camal
The left 4 1/8
" x 4 3/8"
carving reads:
Relief panel of a jaguar eating a heart from the dance platform of the eagles - Chichen Itza
By: E. Camal