During this royal theater date, Elizabeth asks Philip for a favor: she wants him to be on her coronation committee. He says he will, but only if he can be in charge. (He really was chair of the commission, but that appointment happened a year earlier, in April 1952.)
And the jewelry she's wearing here are replicas of real pieces from her collection: two pearl necklaces, the longer of which with its pearl pendant, worn off-center. The shorter of the two necklaces, in real life, was the only piece of jewelry that Queen Mary gave to David; it may be the pearl necklace bought by George V from the estate of Marie Feodorovna of Russia. The bracelet worn on her right wrist is the production's version of Wallis's gem-set cross charm bracelet, which was made by Cartier.
In real life, Princess Margaret wore the Cartier Halo Tiara at the coronation, but the series has substituted a completely different tiara here. I've read that there were copyright issues with reproductions of the Halo tiara. It's understandable, then, that a substitution had to be made, but the difference is really jarring, especially when placed beside the more carefully replicated jewels worn by the Queen Mum.
What did you think of the coronation episode? (Remember: no spoilers for future episodes, please!)