Giving a pair of scissors or knife as a gift is considered bad luck as it said it would cut the friendship in half. To avoid bad luck in the relationship, the gift recipient should give a coin as to "pay" for the gift. It is common for the gift-giver to include a penny, often taped to the blade of the knife, which the gift recipient is to return as "payment". A German scientist named Justus Liebig began experimenting with brewer’s yeast in the 1880s. It was turned into a spread in Burton in 1902, when the Marmite Food Company Limited was formed. The name Marmite derives from a type of French dish, and initially Marmite was sold in earthernware pots. However, since the 1920s it has been supplied in its signature glass jar.