A Few UK Coins Found In Possessions- Honest Opinions?

Thank you kindly Paddy! I may post a few more soon...

We weren't there when it happened, so it's impossible to say. But pennies are gilded for all sorts of reasons: as a science experiment, as a tourist souvenir, as a marketing gimmick, or as an attempted scam in an effort to fool someone into thinking it's an actual gold coin.

As for the rest of your coins: the 1946 florin is made of 50% silver - the last year silver was used in circulation coins in Britain - at current price the melt value is US$5.87. This coin is quite well worn and so I don't think the condition is going to make this coin a collector's item, so it's value is in the silver.

The Churchill crown is notorious for "being an ugly coin". Yours appear in quite nice condition but aren't typically highly sought after by collectors, due to that perceived ugliness. Perhaps a few dollars each.

The 1980 Queen Mother crowns are more sought after than the Churchills but also extremely common and thus not particularly valuable. Again, normally a few dollars each, but the black marks on these examples will make it difficult to attain even that.

The 5p and 10p coins are also in nice condition, but 1968 was the first year of issue and many many people kept nice examples of them. The odd staining on most of these coins pretty much destroys any value above face value they might have had. Also be aware, these coins are now obsolete so actually spending them in Britain might prove problematic.

Just to add clarification, the 5p and 10p coins are obsolete in the UK and shops do not accept them, however banks and the post office will take them at face value, but only paying into an account, not cash for cash.
On the Churchill Crowns, it is not just that they are not an attractive coin, but also that they were produced in huge numbers - something like 34 million I believe. Everybody at the time bought them at face value, convinced they would become valuable in time, but that has not happened. When I ran a coin stall they were brought to me almost every week by people convinced them were going to become rich! Many are now cashed in at face value (25p). They can sell for £1 or £2 to new collectors in decent condition.

Very interesting! My example appears to have the latter on both sides.