aventurine hardening gen.

[Lonely Knight]

Что такое aventurine hardening?

Раздел Траблшутинг мануала по электродвигателю
http://www.worldwideelectric.net/wp-content/uploads/2016/04/Instruction-manual-2014-version.pdf

Abnormality:
Dent and scratch
(a) Indentation (on a race, etc.)
(b) Aventurine hardening
(c) Dents given during handling
(d) Scratches during assembly

типа surface hardening до уровня авантюрина???
мало что гуглится в контексте сталей, типа такого:
...surface be might roughed to aventurine finish...
...the pressure-fixation roll of the invention has an aventurine-like surface with a surface roughness of 0.2 to 3.0 microns....

[paderin]

обработка поверхности по типу облагораживания авантюрина

[johnstephenson]

I suspect it means 'hardening to a point where it becomes as smooth and hard as aventurine', so if there's no equivalent set expression in Ru, perhaps you could read it as meaning 'aventurine-like hardening' or 'aventurine-level hardening'?

That Instruction Manual has obviously been written in/translated into English by several different people, as the English in some sections (such as the front cover) is 10/10, whilst that in other sections (such as the Troubleshooting table) is down to around 7/10. So your table hasn't been written by a native-level English speaker.