Offers have been flooding in from foreign shores for the so-called “Wrekin Ruby” – the giant gem once valued at £11 million but sold for less than one-thousandth of that amount.

Tim Watts, chairman of the Pertemps recruitment agency, paid £8,010 for the ruby, known as the Gem of Tanzania, 18 months ago, and said there has been significant interest since.

The ruby was previously owned by collapsed building firm Wrekin Construction – which claimed it was worth an eight-figure sum – but was sold off by administrators after receiving more than 60 offers.

Mr Watts had planned to split the ruby into smaller gems but has been offered significant sums to sell it on as a whole by enthusiasts in the US. However, it is so large – 10,700 carats – that its quality is near impossible to assess.

Mr Watts said: “We have been offered some interesting amounts of money for it, most of which comes from people in America who are suggesting strongly that we don’t break it up and that they would like to evaluate it and buy it.

“In America they like collecting rocks like that. It occurred to me to metaphorically put a hammer through it and break it up.”

Mr Watts said it remains a mystery how good quality the ruby is on the inside because the tools do not exist to examine it sufficiently and establish that. He explained: “We can’t know because any light that goes in immediately refracts. We are so busy at the moment that I don’t think the ruby has crossed my mind for a year,” he added.

The Birmingham Post first broke the story of the ruby in 2009 when Shifnal-based Wrekin’s accounts for the year ending December 31, 2007, showed the firm bought an item known as the Gem of Tanzania.

It then emerged the stone was previously owned by Michael Hart-Jones, a South African businessman who bought it for £13,000 in 2002. He then sold it to Cheshire-based Tony Howarth in 2006, who sold it on to then Wrekin owner David Unwin for £300,000.

In 2007 the ruby was revalued to £11 million and sold to Wrekin in return for £11 million in preference shares.

Nearly 500 people lost their jobs when Wrekin Construction collapsed and the ruby accounted for a significant portion of the firm’s assets when its bank RBS appointed Ernst & Young as administrators after several contractors called in their debts.