Aircraft Boards, Medium Grade? check out pics

[IMG][/IMG]
[IMG][/IMG]
[IMG][/IMG]
[IMG][/IMG]
[IMG][/IMG]
[IMG][/IMG]

Came across these today at my buddies place. He wants to make some room and get rid of these, but I know nothing about them other than info on them, made by beechcraft an aircraft company.
Only a few boards had gold pin connectors. the majority had what appeared to be silver all over them, or is it just a silver colored base metal?

it appears to be low grade to medium, if it has any gold contacts on them or from what I see hardly any ic ships on them, and the tracing looks like silver... I would put these in mid grade to low.

I would guess tin or lead on the coatings. I would think low grade. Even still, worth more than tossing out.