Queen Letizia has worn a very special but rarely seen set of jewellery for an important royal event.

The diamond and sapphire necklace was a wedding gift from her parents in law, King Juan Carlos and Queen Sofia, but it hasn’t been worn publicly for almost twenty years.

The last time it was seen was at the glittering reception held in Madrid on the eve of the wedding of the then Prince Felipe and Letizia Ortiz.

However, as the now King Felipe and Queen Letizia hosted the annual diplomatic gathering at the Royal Palace in the Spanish capital, the gems were one again on show.

The Queen of Spain’s necklace is a simple design featuring the blue stones and sparkling diamonds that twist down to hold a giant pearl pendant.

Eagle eyed Spanish journalists, including royal commentator Nuria Tiburcio, spotted the gem as the royal reception unfolded.

The necklace was a particularly sentimental gift from King Juan Carlos and Queen Sofia to their daughter in law. The gem had originally been given to Sofia for her own wedding.

However, the long hidden necklace wasn’t the only talking point when it came to Queen Letizia’s jewels. One of her bracelets came loose as she was greeting some of her guests and fell to the floor. King Felipe helped her to refasten it.

The annual reception sees the King and Queen greet the diplomatic body accredited in Madrid which currently consists of 126 embassies and around 800 consulates.