That's wonderful you are there during Jubilee weekend! I thought about going too, but I dreaded the crowds. I just got back from London a few weeks ago. Another place to go if you like jewelry exhibits is the V&A. They have two rooms packed with jewelry from the ancient times to present day. Those rooms always give me inspiration for jewelry designs. There is a gorgeous peony brooch and of course, Beyonce's butterfly ring on display. After the V&A, head across the street to Harrods Jewelry Hall! It's a feast for the eyes if you have never been. I guarantee you will love the Jewelry Hall.
Speaking of the Jubilee, when I was there a few weeks ago, of course I had to go and stock up on Jubilee souvenirs!

This is the official shop and worth going to:
Search results for 'platinum jubilee' (royalcollectionshop.co.uk)
You may be a Brit, and already know all about this. I was definitely in Jubilee tourist mode shopping when I was there.

Even got me fruitcake to go with my tea! By the way, if you're a tea drinker, they have some nice tea sets.
I am so excited for you going to the Jubilee!