This is the house 0.50p chip from the Hard Rock casino in Manchester. I would suspect that it will be the same chip they use in London as it does not have any location information on it. It is a ChipCo chip and is used on the BlackJack/Roulette tables as house chips.

They also have £2.50 chips but still seem to use the 0.50p chips when (in the unlikely event) that you get a blackjack.

I can also tell you a lot about the Nova Scotia cards that you have up. The middle one is the normal card used in their slot club. The bottom (crown) card is their premium card. It gets you access to a special room as well (oddly enough called the Crown Room) where they serve small food items and free drinks. The two Nova Scotia locations use the same card but not the same numbers. The Halifax card is not transferrable to Sydney.