(And my thanks to Gary Kennedy who brought it to mind.)

Two things you might need to know about both cleaning up knives and them keeping them in place. Let me give you my thoughts on the cheap way first and then the fancy pain-in-the-tuchas expensive way.

CHEAP:

Shoe or furniture polish and OOO or OOOO steel wool will make a lot of your collectable finds,(knives), look and feel a lot better then they do coming from the flea market or garage sale. For example black shoe polish on cast iron is
the way museum pros do it. For that
matter, brown shoe polish makes a very respectable furniture polish. (NEVER use the spray can stuff w/ silicone
on something you think you might EVER want to refinish.)

And if you want to make sure your knife / collectable what-sits stays on the shelf during earthquakes or visits from the grand-kids, I recommend the sticky / handy-tack stuff from the office supply
store /aisle. (Also great to stick your
computer's speakers to the top or your monitor and such-like.)

EXPENSIVE:

For careful cleaning & polishing, you need micro-crystalline wax. Check out... Restoration Preservation Conservation Products They have all kind of
chemicals for taking care of valuable collectibles and I'm sure some would begoodonknives. Ain't cheap though!

(Gary sez Bill Powell offers the stuff.)

For keeping things where they belong -all museum and curatorial like- check out Museum Quake Wax from Conservation
Resources International LLC They have
all manner of acid-free, archival curatorial stuff. And they too ain't cheap!

Bill