Theriac stamp made of wood and metal, with handle and brass plate depicting Madonna and child flanked by winged lions of St. Mark, from Venice, Italian, 1601-1800

Theriac was a thick syrupy liquid medicine (known as an electuary) made from as many as 64 different ingredients. Variations of it were made over the centuries in a number of different cultures and it was used as a cure for many illnesses until the end of the 1700s. The ingredients were often strange and exotic. For example, in some recipes the flesh of snakes was considered essential.

It was a highly prized and extremely expensive product. To prevent fake theriac being sold, cities such as Venice, Toulouse and Montpellier prepared theriac in public under official supervision. This stamp was probably used to confirm that the medicine was genuine. The seal has the words “Alla speciara della Madonna.therica fina in Venezia” embossed on the rim. This translates from Italian as “From the pharmacy of Our Lady...the finest theriac in Venice”. The stamp shows Mary and the Christ child with the winged lions of St Mark on either side.