Peebles Hoard features tin-enriched bronze – The History Blog
https://www.thehistoryblog.com/archives/74399
"This likely suggests that a rarely observed technique was used in the creation of the Peebles Hoard. Rather than tin plating or tin dipping, this probably represents a deliberate surface enrichment of the bronze where the tin was drawn to the surface. It is a remarkable and rarely observed process from Bronze Age Britain that requires more work to understand."