Why these squiggly sketches are worth a small fortune - and how a humble PING PONG BALL holds an unexpected  place in Royal history...

• e-mail

Most of us would have struggled to make much of the colourful daubs presented to last night's Antiques Roadshow in Swanage.

Were they an outline for a Viking ship, perhaps, or plans for a curious piece of modern architecture?

But renowned jewellery expert Geoffrey Munn was in no doubt: the watercolour illustrations were original designs for the coronet worn by Charles, Prince of Wales, at his 1967 investiture - and the round thing in the middle would turn out to be a ping pong ball sprayed with gold!

The paintings themselves, he said, were worth £8-10,000 at auction.

Roadshow viewers were confronted with colourful daubs and squiggles which turned out to have a royal - and rather valuable - history

They were original designs for the coronet worn by the 20-year-old Prince Charles at his  1969 investiture as Prince of Wales

Charles was anointed Prince of Wales by his late mother, Queen Elizabeth in a televised ceremony at Caernarfon Castle, in Gwynedd, then Carnarvonshire, in 1969.

The designs for the coronet - the centrepiece  of the Investiture - were brought to the Roadshow in Dorset by relatives of the designer, goldsmith Louis Osman

Geoffrey Munn said that the designs had not just historical value but particular rarity as most original jewellery designs are discarded.  

Described as a modern take on a traditional form, the coronet had been presented to Elizabeth by the Worshipful Company of Goldsmiths.

The 20-year-old prince wore his uniform as Colonel-in-Chief of the Royal Regiment of Wales as he knelt on a pedestal in front of his mother.

A centuries-old ceremony followed, which involved the Secretary of State of Wales reading Letters Patent in Welsh while the Queen bestowed upon Charles five pieces of insignia: a sword, ring, a gold rod, a kingly mantle and a coronet.

The prince then took an oath: 'I, Charles, Prince of Wales, do become your liege man of life and limb and of earthly worship and faith and truth I will bear unto thee to live and die against all manner of folks.'

Charles gave a speech in both Welsh and English.

After kissing his mother on the cheek, the Prince was led onto the balcony of the Queen's Gate to greet the crowds waiting outside the castle.

More than 4,000 guests were invited to the ceremony, with millions more watching on television. An estimated 19 million people tuned in to watch in Britain, and 500 million worldwide.

Speaking on the roadshow in Swanage, Dorset, jewellery expert Geoffrey Munn said that the designs  could be expected to fetch between £8000 and £10,000 at auction

The couple who brought the piece along were related to the original designer of the coronet 

The futuristic coronet was a gift from the Worshipful Company of Goldsmiths to  Queen Elizabeth II

The title Prince of Wales has traditionally been bestowed to the male heir apparent of the English or British Monarch since Edward I of England gave his son Edward of Caernarfon the title in 1284.

Given the historic nature of the role, why was a new coronet needed in 1969? 

The answer is that the existing coronet - the  Coronet of George, Prince of Wales -  had gone into exile with the Duke of Windsor. This was yet another controversial decision from the man who was briefly Edward VIII but abdicated to marry Mrs Simpson. 

His younger brother, George VI, grandfather Charles, had never been Prince of Wales.  

It was judged impractical to charge the the Duke of Windsor with stealing the coronet, which was eventually returned to Britain after he died in 1972.

Since the 1902 coronet was unavailable, and the Coronet of Frederick, Prince of Wales was judged unusable due to its age, a new coronet had to be made for the investiture of Charles.

Charles was invested as Prince of Wales by the late Queen Elizabeth II on July 1, 1969, in a ceremony at Caernarfon Castle. The sphere at the apex of the coronet is a gold-plated ping pong ball

The Prince, who was 20 at the time, decorated in his uniform as Colonel-in-Chief of the Royal Regiment of Wales, knelt on a pedestal in front of his mother for the historic ceremony

The Prince of Wales, later King Edward VIII, wearing his coronet and investiture robes in 1911

Though based on a traditional design, the new coronet had a futurist look - and a faintly bizarre backstory.

At the time, makers were unable to find a round piece of gold to fulfil the design so instead sprayed a ping pong ball with gold before engraving it with the Prince of Wales' insignia.

The coronet is now on permanent display at the Tower of London.