If you are passionate about luxury skincare, you know first-hand that the packaging is an integral part of the consumer experience. Chances are you’ve already come across these fancy black glass bottles and jars, commonly referred to as “ultraviolet glass” – but this is only a colloquialism. ‘Ultraviolet’ refers to the corresponding frequency of light waves, but the correct name for this high-end packaging material is Miron glass, or simply violet glass. And while they might look super slick, do they serve more than just an aesthetic purpose?

What is the purpose of using differently colored glass?

The sun emits light that is beneficial; it’s responsible for the growth of most living things. But too many sun rays can change from beneficial to quickly deteriorating – just as a healthy vitamin D sun soak can quickly turn to a burn. And it’s the same with cosmetics, which is why the packaging matters when investing in your beauty products.

A container’s colour is important because it determines which type of light (as categorized by the light spectrum) will be able to penetrate the glass. Unsurprisingly, the transparency of clear glass offers no protection from light.

Let’s take beer for example: beers that become spoiled by sunlight are what brewers call “lightstruck” – a light-induced reaction that changes the beer’s odor into a stench similar to that of a skunk.¹ This is the main reason you see beers in amber bottles; the darker amber glass blocks enough light to almost completely stop skunking.

Compared with blue, green, amber or clear glass, violet glass provides a host of benefits including:

• Extended shelf-life
• Protection from decomposition
• Natural protection properties
• Revitalizing effect on organic life
• Beautiful packaging
  
  

One of the main benefits of violet glass is that it’s a natural filter: blocking out the damaging spectrum of visible light (excluding ultraviolet and infrared). A Dutch company, MIRON Violettglas, has done studies to demonstrate the preservative properties of ultraviolet glass. They used brown, clear and violet glass to store away chives for 3 months. After exposure to sunlight, the chives were measured by their freshness in texture, color and aroma. The result:

Cosmetics that benefit from Miron or violet glass packaging

In recent years, the beauty industry has adopted ultraviolet glass as the highest standard. It might also seem a little counter intuitive (it was for me, at least), that violet glass permits UV light. Because aren’t UV rays something to be cautious of – and the whole reason that we should be wearing sunscreen?

In short, yes. But UV light also suppresses microbial growth because it’s a sterilizing agent.² In the field of cosmetics, this would translate to products with fewer preservatives and antimicrobial ingredients that can still uphold freshness.

Improperly storing or exposing products to direct sunlight may put them at risk. This can easily happen in transport, in-store or in your very own bathroom. This, however, depends on what the product is, its ingredients and its packaging. For example: products with antioxidants like vitamin C are known to be photosensitive. They can degenerate in only a matter of hours if exposed to intense sunlight.

In some cosmetics, the effects of sunlight can lead to increased bacteria growth, or even an altered cellular structure of a product. This ends up affecting their quality, efficiency & shelf-life – sometimes completely nullifying all of their potential benefits.

Preservative-free cosmetics are vulnerable due to the higher chance of bacterial contamination, as photosynthetic bacteria thrive in sunny conditions; these bacteria may even grow large enough to destroy any products which don’t contain preservatives. Taking into consideration that many natural & organic cosmetics contain little to no preservatives, appropriate storage is very important. For this, violet glass is most optimal.

The unique properties of ultraviolet glass – being a natural filter blocking out visible light – improves the durability & quality of cosmetic products. And although it makes a lot of brands look more or less the same, Miron glass actually plays a significant role in the preservation of product quality and shelf-life. But don’t worry if your favourite skincare or beauty products don’t come in violet glass packaging. You can still maximise their efficacy by storing them in a cool, dry spot – away from direct sunlight.

What do you think about Miron glass – even if it has benefits, is it still just a hype?

Let us know your thoughts in the comments below!

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Resources:
1. Beer lightstruck flavor: The full story
2. Light as a Broad-Spectrum Antimicrobial
3. Miron Violettglas