Hi guys

I’m an Irish plumber/gas/heating engineer living in London, UK. I’m well used to cashing in my scrap which I consider a perk of my job ie. the brass and the copper.
I’m looking at getting into something new as a kind of a hobby- scrap pcbs- printed circuit boards & extracting what’s good out of them ie. the gold - but anything else on them that’s worth money. I’d just like some help, initially identifying the different components & what they are made of.
Thanks in advance, anyone who can help - apologies if I’m slow replying as always busy 👍