Our amber coloured bottles may be prized as decorative, but actually that amber colour has a practical purpose. A number of medicinal or kitchen ingredients have a tendency to degrade upon exposure to light, so the dark colour of amber glass bottles screens out harmful UV rays to offer a protective, preservative effect. Amber is more effective than green or blue glass in its protective effect.
How amber glass bottles are made
While early glass makers were obliged to find techniques for filtering out impurities in the raw material to create clear glass, coloured glass later became prized for its decorative properties. There are various methods used to colour glass, usually involving chemical additives, but an amber effect is generally created by adding ions during the manufacturing process. Sulphur, carbon and iron salts result in iron polysulfides that impart an amber tint to the glass. This can range from a warm yellow to very dark brown, almost black. Occasionally silver has been used to obtain the same effect and cadmium was once used for a similar yellowish tint, however its toxic properties saw it fall out of favour. Similarly, manganese compounds produce a beautiful and highly prized amethyst tinted glass, iron or chromium make green glass, copper produces vibrant turquoise glass and cobalt results in the very popular blue glass.
Amber glass bottles in history
Amber coloured bottles were in wide use during the 19th and 20th centuries. Early beer bottles were commonly amber in colour to preserve beer from light degradation. Early glass making techniques involved mixing compounds manually, resulting in wide shade variations. As glass production graduated to automated techniques, the colour range became more uniform. These days amber is used particularly to preserve medicinal liquids from light. Aromatherapy oils and cosmetic lotions are often best stored in amber glass bottles and jars, while modern beer is still best when protected from excess light.
The Wares of Knutsford range includes amber jars for cosmetic creams and lotions, along with medicine bottles and dropper bottles, plus amber glass beer bottles for home brewers. Sizes range from 5ml to one litre, with a choice of caps. Remember there’s a fixed delivery charge no matter how large your order, so benefit from economies of scale and order in bulk and don’t forget to sterilise your bottles and jars before you fill them. Take care to label the contents carefully for safety and convenience.