In Don't Starve Online, you can refer to the following for useful ancient technological materials in Don't Starve:
The ancient technological materials that are useful in Don’t Starve Online include the following types of ancient technological materials:
Thulium ore fragments: 6 thulium ore fragments = 1 thulium ore
Thulium Ore: Non-renewable. It can be obtained by smashing statues, opening boxes, smashing thulium ore, synthesizing, etc.

Demon Fuel: Kill Shadow Monster, Nightmare Petal

Living wood: can be killed by killing trees

Rhino horns and eyeballs: Rhino horns are obtained by killing ancient rhinos, and eyeballs are obtained by killing giant deer.
Gems: Open treasure chests

Cane, pickaxe and axe