Propolis is a natural resinous mixture produced by bees from substances collected from parts of plants, buds and exudates. It possesses a characteristic and pleasant aromatic smell and varies in colour. Cornish black bees produce a dark red/brown coloured propolis, but in small quantities of around 10g per colony per year. It is a scarce and valuable substance.

Bees use propolis in the construction and repair of their hives – for sealing  openings, cracks and smoothing out the internal walls and as a protective barrier against external invaders, or against wind and rain. They also use propolis for its high antibacterial and anti fungal activity.

In Italy, propolis was used as a violin varnish by Stradivari- it must be good