Alum, More Precious than Gold - Sydney Thorne

Never heard of alum? You’re not alone.Yet, for centuries, alum was vital to the production of coloured cloth. Alum was needed to fix dyes and colours to the cloth. Without alum, the colours ran and faded. With alum, they shone and were fast. As a result, as the Italian scientist Vanoccio Biringucci put it in the 16th century, alum was as ‘essential to dyers as bread is to man’. Corner the market in alum, and you could make a fortune.Manufactured from a rock called alunite that was mined in... Zobrazit více