well ANYTHING recycled in bulk can get you the Bell...LOL...just saying....of course there is value, it is a precious metal. You just have to have a large enough supply to make the $$$ you want to make....ie a box ain't gonna do it
A gaylord or 2, well now your are talking. From my reading, only the very tip of the plug is platinum, gold or palladium....and the whole reason they get changed out is they have worn out. Their always is SOME residual left, but it would have to be very very little.
These guys had a thread on it and a diagram that shows the part that has the PM
Platinum recovery/Spark plugs
Alot of newer ones have iridium. I did a quick search and the goldrefining forum had some posts that estimated about 80 plugs CAN yield about a gram...YMMV of course. Do some more research and see if the iridium is worth it along with the rest and then do the math.
Bookmarks