1. Amber (Brown) Glass Bottles
- Best UV Protection: Amber glass blocks over 90% of UV rays, making it the industry standard for essential oil storage.
- Wide Applicability: Suitable for all essential oils, especially light-sensitive ones (e.g., citrus, mint), effectively slowing oxidation and evaporation.
- Scientific Basis: Its dark coating absorbs specific light wavelengths, reducing photochemical damage to active compounds in oils.
2. Cobalt Blue Glass Bottles
- Moderate UV Protection: Blocks about 70%-80% of UV rays, slightly less than amber, but offers a more aesthetically pleasing look, ideal for premium brands.
- Special Use: Some manufacturers add cobalt (not ordinary dye), extending shelf life by over six months.
3. Green Glass Bottles
- Basic Protection: Blocks 50%-60% of UV rays, suitable for less light-sensitive oils (e.g., some woody notes).
- Eco-Friendly & Appearance: Marketed as an eco-conscious choice with more uniform color than amber, but protection is limited.
4. Clear Glass Bottles
- No Protection: Transparent glass cannot block UV rays, leading to rapid oxidation and spoilage. Only suitable for short-term display or when paired with an external aluminum cover.
- Use Case: Common in low-cost packaging or to showcase oil color, but requires prompt use and strict light avoidance.
5. Other Colors (e.g., Purple, Black)
- Niche Options: Purple glass (e.g., UV glass) converts UV light to visible light, offering dual protection and maintenance, but is costly and rare.
- Ultimate Protection: Black glass nearly blocks all light, though it may hinder oil inspection. Primarily used in labs or for special storage needs.
