The late movie icon's jewels were on display at the bash on Tuesday night (19Feb13) - but Moore actually got to wear one of the star's most famous pieces - a gift from her husband Richard Burton.
Taylor wore the gems onstage at the Oscars in 1967 when she was named Best Actress for her role in Who's Afraid of Virginia Woolf?
Bulgari jewellery experts purchased the necklace at a Christie's auction in 2011 for more than $6 million (£3.75 million).
Moore said, "It's so lovely to be able to wear something like this. It has so much sentimental value and is obviously such a beautiful, exquisite piece. It's really a work of art."
Among those left stunned by Taylor's jewels were fellow guests Drew Barrymore, Kirsten Dunst and Naomi Watts, who is nominated for an Academy Award this Sunday (24Feb13) for her role in The Impossible.