Ebony: it is carbonized wood, and plants and creatures on the ground are buried in low-lying places such as ancient riverbeds by earthquakes, floods and mudslides. Some trees buried in mud were formed by carbonization for thousands of years under the conditions of hypoxia and high pressure and under the action of bacteria and other microorganisms.
Ebony: Guibourtia is just wood for planting trees. No burial and carbonization.