/ stone axe can be crafted with the following recipes

Autolearned
Player Recipe
Primary skill used: survival(4)
Required skills: fabrication(1)
Time to complete: 60 minutes
Tools required:
> 1 tool with hammering quality of 1
> 1 tool with soft hammering quality of 1
> 1 tool with wood chiseling quality of 1
Components required:
> 1x stick OR 1x plank
> 1x flaking rock OR 1x flint
Byproducts:
(none)

Autolearned
Player Recipe
Primary skill used: survival(5)
Required skills: fabrication(2)
Time to complete: 120 minutes
Tools required:
> 1 tool with hammering quality of 1
> 1 tool with anvil quality of 1
> 1 tool with wood chiseling quality of 1
> nearby fire
Components required:
> 1x stick OR 1x plank
> 1x rock
> 1x water OR 1x clean water OR 1x sewage water OR 1x salt water OR 5x saline solution
> 1x sand OR 1x gravel
Byproducts:
(none)
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This recipe can be found in the following books when survival is at least the required level:
Outdoor Adventures (level 1)
Survival Under Atomic Attack (level 1)
Engineering 301 (level 2)