Quarterly silver production also jumped 105.3% on the year to 32,748oz, with both precious metals recovered from 34,839 tonnes of mined ore, down 26% year-on-year, and 44,746t of processed ore, mostly steady on the year.

The average quarterly gold grade rose 45% year-on-year to 8.8g/t, while the silver grade was up 80% at 27.7g/t.

Gold recoveries remained stable year-on-year at 95.4%, while silver recoveries increased by 6.5% to 81%.

Trans-Siberian achieved gold revenue of US$15.7 million for the quarter, 3.2% higher than a year ago, with 11,949oz of gold sold, up 5.6%, at an average price of $1,312 per ounce, which was 2.3% lower than the March 2018 quarter.

Silver revenue for the quarter climbed 30.6% on the year to $563,000, with silver sales up 43.3% to 36,329oz at an average price of $15.5/oz, down 8.9%.

The company said it was on track to meet full year production guidance of 40,000-44,000oz and was also on schedule to complete the construction of the underground de-watering pumping facilities in May.

Trans-Siberian's shares (AIM:TSG) were trading 5.51% higher Monday at 58.56p (USc), up 56.2% in the past six months.