The historic jewel was previously sold by a London dealer to an overseas buyer but was blocked from export by the government in 2015.
The coronet was gifted to the museum by Irish- American financier and hedge fund manager William Bollinger, who bought the piece for an undisclosed seven-figure sum.
The coronet was designed by Prince Albert in 1840, the royal couple’s wedding year, and was based on motifs which appear on Albert’s coat of arms. The whole is symbolic of eternal love. Victoria wore it for the first of her portraits by Franz Xaver Winterhalter painted in 1842.
It was passed down to Princess Mary in 1922 but subsequently left the royal family after a private sale.
The coronet will go on public display as the centrepiece of the museum’s William and Judith Bollinger Jewellery Gallery in 2019.