Caledonian Alloys, the world's largest recycler of aerospace metals, saw pre-tax profits rebound fourfold to $1.39million (£920,000) despite depressed metal prices.

The US-owned company, which saw profits almost wiped out in 2013 in the volatile metal market, "responded positively" in the year to March 2014, according to latest accounts just filed at Companies House.

The recovery came "despite facing challenging conditions with regard to falling nickel prices on the London Metal Exchange, a 15% reduction compared with last year", the directors write.

But profits were still at barely a fifth of the 2011 and 2012 levels of over $6m (£4m) recorded by the Livingston-based business. When sold to Oregon owner Precision Castparts in 2007, Caledonian had just made a £17m profit on turnover of £95m.

The sale triggered a pay-out said to be worth £100m to co-founders Ron McNab, Doug Sked and Hugh Stewart. Only Mr Stewart has maintained a high business profile, setting up investment vehicle Coralinn which has backed businesses such as Clyde Space, Allcord, iPort Software International, and TOM Vehicle Rental, where Mr Stewart is chairman.

The accounts show that in the past three years, staff numbers at Caledonian Alloys have been cut from 138 to 109.

Turnover however rose last year from $80m to $107m (£53m to £71m), more than twice its £33m level in 2010 after the US group switched some of its business to sister companies within the group. It took a £18m dividend from the Scottish operation five years ago but has not been paid a dividend since.