Weardale Fluorspar is the rarer variant of Derbyshire Blue John stone. It is a semi-precious mineral or fluorspar recognised by its beautiful radiating crystalline structure, which was only mined at Weardale in the Northern Pennines. In the 18th Century Weardale was one of England’s main source of minerals such as Lead ore ( Galena ), Fluorspar ( Calcium Fluoride ), Sphalerite ( Zinc Sulphide), Quartz, and Calcite. These minerals were formed over 255 million years ago when the Granite dome under the Dale expanded allowing hot chemical solutions to be rise up into the overlying limestone’s. These solutions crystallised out in the cracks in the limestone’s where they were mined from Roman times from what was known as the North Pennines Ore Field. Mining has now ceased but the attractive & incredibly rare crystals are highly prized by mineral collectors. In the 18th Century local lapidaries probably began to make ornaments from it such as decorative vases. Specimens were coveted by the French Royals whom adorned them with ormolu mounts. The deposits are not found as a single mass, rather in veins each with its own unique banding and colour, from beautiful shades of rich green through to creamy yellows and white.
Fredrik Ludvig Rung, born July 20, 1758 in Stockholm, died February 1, 1837 in Stockholm, was a Swedish sculptor, chief student and professor. He was the son of the guardian age man and captain of Stockholm’s bourgeois infantry Fredrik Rung and Anna Sophia Wester. He was married for the first time with Anna Charlotta Pfeffer and the second time with Sophia Ulrika Pfeffer. He studied at the engineer Olof Årres school in Stockholm and at the Royal Academy and during study trips to Germany, the Netherlands and England. He was appointed Hovciselör in 1779. From 1791 he became a shareholder in Älvdalen’s Porphyry and was one of the early 19th Century’s most dominant producers of Bronze mounted Älvdalen’s Porphyry production. Rung belonged to the group of artists who worked under Louis Masreliez at the room decor at Stockholm Castle in the latter part of the 18th century.