To the best of my recollection, no queen consort who was crowned (since the Restoration) has ever again worn her coronation crown after that event.
However, last century both Queen Mary and Queen Elizabeth wore their crowns without arches, on a number of occasions for state openings of parliament.
And I'm pretty sure we will not be seeing the gold coach!
The reign of George VI included all the years of WWII and austerity, when parliament was opened without pomp.
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