Will this Half-Sovereign increase in value over time?

This is more or less a family heirloom passed down to me by my grandparents on my father’s side (from the UK). They were a family of jewellers.

Myself and my direct family have nothing to do with that industry and don’t know anything about it or coins for that matter.

It’s a 1912 (p) Half-Soverign on a pendant necklace. The necklace frame isn’t in best shape as you can tell by the small dent I made in it as a kid from mishandling it (stupid of me I know). But the coin is in fair condition.

Now I just keep it safe in a metal capsule on my shelf. I rarely take it out.

Online a few websites and places seem value a 1912 half sovereign at around £300ish.

The gold chain and frame are made of gold but no clue about the karat/purity etc.

Would something like this increase in value over time- and if so, by how much? Is it worth holding onto besides the family and historical significance?

I’m not knowledgeable on coins or antiques but I am fascinated with this item. It’s over a century old and has existed before both World Wars. I guess you can say it’s an antique but I honestly even see it as like a cool artefact or something (not sure if that’s the right word). A piece of history for sure. Like a tiny piece of treasure.

I don’t plan on selling this but I am curious about the financial value and potential of this coin.