With Noel's question about kangaroo leather I would like to bring up
another issue.  My understanding about leather is that depending on
the tanning process will determine how long the leather will last.
Is it true that leather that is vegetable tanned will not last as long
as leather that is chromed tanned?

The other issue that I understand is that chromed tanned leather should
not be used if it comes in contact with metal.  Has anyone on the list
verified this through tests that the chromium salts in the leather does
react with the metal surfaces of the valves and vegetable tanned
leather does not?

I have seen the issue with new leather nuts but never on metal valve
plates.  All of the players I have seen were still running on there
original 1920 valve leather when I receive them.

I will always use vegetable tanned leather if it comes in contact with
any metal.  I just wanted to make sure that others are made aware that
there are differences.  Most leather made today is chrome tanned.

Pete Knobloch
Tempe, Arizona