Geoff Turnbull, whose dark blue and pink colours were associated with high-class pair Lord Glitters and Mondialiste, has died at the age of 74.

Turnbull was a successful businessman who founded the GT Group of companies, a business in the environmental engineering sector that generated an annual turnover of more than £50 million and employed 300 people.

His involvement in ownership began when he purchased La Sylphide as a Christmas present for his wife Sandra in 1998. The daughter of Rudimentary won seven times for the Turnbulls between 2000 and 2004 before retiring to become the pair’s first broodmare

Top-level success came in 2015 when Mondialiste struck in the Grade 1 Woodbine Mile and the following year there was another impressive victory in North America for the David O’Meara-trained charge as Mondialiste added the Arlington Million to his record.

At Royal Ascot last year, the Turnbull silks were carried to victory by Lord Glitters in the Group 1 Queen Anne Stakes, defeating Beat The Bank by a neck.

It was in 2014 that the decision was made to move the Turnbulls’ Elwick Stud operation to Sheraton Farm, just a mile away from their family home where their stock had been based.

Significant investment was made in Sheraton Farm, including the building of a stallion standing facility for when Mondialiste retired from racing. It is home to a band of over 80 horses.

Mondialiste took up stallion duties in 2018, at a fee of £6,000, and his first yearlings are set to go under the hammer this autumn.

In a statement posted to its Twitter account, Elwick Stud said: “Elwick Stud is deeply saddened by the passing of our much loved CEO, Geoff Turnbull MBE after a short battle with illness.

“Black armbands will be worn during the racing today as a mark of respect for Mr Turnbull, who was a great ambassador for northern racing.

“We ask that the privacy of the family is respected at this very difficult time.”