I'd really like to see more images!
The top part looks like early Mdina, the bottom part doesn't.
I can't work out if it says "Present from Malta! With all our love, Mike, Betty, Timothy and Jonathon.", or Kate, Betty, Timothy and Jonathon.
I know Michael Harris was known as Mike, I don't know if his wife Elizabeth is ever known as Betty, (she signs my Christmas card "Elizabeth", but that might be her way of doing the Collectors' Club cards - close personal friends might be different), the sons are Timothy and Jonathon.
I can't work out what colour the bottom part is, exactly, or how the colours work in it, or how they work in with the top part.
I'd like to see a pic of the inside of the rim - to see how the layers of glass work together, and to see if there are manufacturing or tool marks in it.