A piece of the royal wedding cake of Prince William and Kate Middleton has sold for $4,160 (£2,588) at an auction.

The eight-tiered wedding cake, made by pastry chef Fiona Cairns and her team, went under hammer at California-based auction house, Julien's Auctions. A representative of the auction house has confirmed the selling price but not disclosed the buyer's identity, according to E! News.

Prince William and Kate Middleton married on 29 April, 2011 at Westminster Abbey. The wedding cake was as much important ingredient of the nuptial as the wedding dress of Kate Middleton.

Of the cake's total slices of 650 offered to the wedding guests, a piece was sold at another auction in May last year.

Kate's personal touch to her wedding cake

The grand sweet fruit cake of William and Kate's wedding was adorned with fine details of flowers, petals, leaves and other embellishments. A piece of lace from Kate's wedding dress put onto the cake added a personal touch to it.

According to Cairns, the whole cake was Kate's idea. Catherine gave ideas for floral decoration of the wedding cake and she also planned the wedding.

"It was all her idea. She's a very creative person and that's why it was so special. A lot of people thought the royal wedding was a very grand affair but it was also very personal," Fiona Cairns told HELLO! Online in a recent interview.

"She (Kate Middleton) gave me a list of 17 different flowers and leaves that she wanted on the cake, and told me afterwards that she didn't mean all 17," Cairns said.

"Each flower had a meaning to her and every part of the cake was very personal."

Cake gives clue to William and Kate's baby plans?

The top three tiers of William and Kate's wedding cake were removed at the time of the wedding and preserved for the future. Later, the part original part replica royal wedding cake of was put on display for the summer exhibition at Buckingham Palace in July 2011.

"We were always told that the cake would be saved for the future. It's always been a tradition and that's why the cake was fruitcake, because after 30 months it's even more delicious," Cairns added.

Of the three tiers, the top most tier of the cake was served to guests on the occasion of Prince George's christening last month, hinting at the Duke and Duchess of Cambridge's plans to have two more babies.

While speculation about three babies for William and Kate may be a faraway thought, reports claiming the royal couple's plans for second baby surfaced soon after the birth of Prince George in July. The reports said that William and Kate will announce about Kate's second pregnancy at Sandringham House in Norfolk during Christmas.

Meanwhile, royal expert, Jeremy Fine, has revealed that Kate has told her friends that she hopes to have at least three children.