One of the first things new hunters want to know is: what does it mean when you find a certain colour? Is it rare? Is it valuable? Should you be more excited than you are?
The answer depends on the colour, and here’s everything you need to know.
Why colour matters
Every piece of sea glass was once something. A bottle, a jar, a ship’s lantern, a medicine vial, a piece of Victorian tableware. The colour tells you what it used to be, roughly when it was made, and how likely you were to stumble across it on a UK beach today.
In the UK, the most common finds are white, green and brown, the everyday workhorses of coastal glass history. Everything else is a bonus. And some of those bonuses are genuinely extraordinary.
Here’s how to read what you’ve got.
Every day finds – Common
Green
The most abundant colour on any UK beach. Green comes from beer, wine and soda bottles, the backbone of British coastal dumping for centuries. Kelly green, olive green, dark bottle green. Beautiful in its own right, and lovely for jewellery, but you’ll never be short of it.
Brown
Brown comes from beer bottles, old medicine bottles and some food containers. Warm, earthy, often nicely frosted. Common, but always worth picking up a good quality piece.
White / Clear
Clear glass comes from old jars, clear plates and soda bottles. Looks simple, but a thick, perfectly frosted white piece is genuinely satisfying to hold. Worth noting: some clear glass that’s been in the sea a long time develops a faint lavender tint. More on that below.
Worth getting excited about – Uncommon
Sea Foam Green
That soft, pale minty green. Most sea foam green comes from bottles, most famously the iconic Coca-Cola bottle, and it has a finding ratio of around 1 in 50. It photographs beautifully and makes stunning jewellery.
Soft Blue / Pale Aqua
Sea foam and aqua often come from antique soda bottles and milk glass items. On UK beaches, these shades feel special every time. Pale blue in particular has a magical, almost translucent quality in the light.
Amber / Golden Amber
Not to be confused with common brown. Genuine amber sea glass has a warm, earthy golden tone, with some pieces dating back to the early 1900s, when whiskey, snuff, and bitters bottles were commonly made in this colour. Worth a second look when you think you’ve got brown.
Getting rare now – Rare
Cobalt Blue
One of the most popular colours among collectors, cobalt blue is considered rare and is not often found on UK beaches. Around 1 in 200–300 pieces found will be cobalt blue. It came from vintage medicine bottles, perfume bottles and art glass, where that deep, rich blue was used to signal that a bottle contained something potent or precious.
Lavender / Purple
Most lavender sea glass comes from clear glass bottles made between 1880 and 1915 that contained manganese as a clarifying agent. When the glass was exposed to UV rays for decades, it turned from clear to a soft purple. Finding a piece of genuine lavender sea glass means you’re holding something that’s been slowly transforming in the sea for over a century.
Pink
Pink sea glass is a soft pastel, often more accurately described as peach, and most likely comes from Depression-era glassware that was widely used in household items. Rare, delicate and highly sought after for jewellery.
Extraordinary finds – Ultra Rare
Red
Finding a piece of red sea glass is like discovering treasure. These rare gems come from early 1900s automobile tail lights, ship lanterns and certain decorative glassware. Due to the high cost of producing red glass, fewer items were ever made with this colour. If you find a red piece, sit down for a moment.
Orange
Orange is considered the rarest sea glass colour, mainly because very little orange glass was ever made. Most orange sea glass likely comes from decorative tableware, art glass and vases. A quality orange piece in jewellery-grade condition is genuinely extraordinary.
Turquoise
Turquoise is distinctive from other blues by its almost electric colour and is found in older glass items, particularly from the early 1900s and earlier. It was less commonly used in mass-produced items, often being found in art glass, ornate bottles and window panes.
Black (Pirate Glass)
Probably the most overlooked sea glass of all. Black glass, known as pirate glass on account of its age, was commonly used in the 18th and 19th centuries by seafarers to keep light out and preserve rum and ale aboard ships. It can appear as ordinary beach pebbles until you hold it to the light, where dark olive green or amber reveals itself inside. Seaham is one of the best UK beaches for finding it.
Multi-coloured (End-of-Day Glass)
Unique to a handful of beaches, most famously Seaham. End-of-day glass was made from leftover molten glass at Victorian factories, poured together in swirling combinations at the end of a shift. Finding a multi-coloured piece is like finding a small piece of industrial history.
A note on fake sea glass
As sea glass becomes more valuable, fake sea glass is increasingly common. Genuine sea glass is heavily frosted and pitted from salt exposure, rounded, and often triangular in shape. Fake sea glass, produced by artificially tumbling glass, is smooth and unfrosted. If someone is selling identical earrings in the same size, shape and colour, there’s a good chance it’s tumbled glass rather than the real thing.
What to do when you find something special
Bring it home, rinse it gently in fresh water, and hold it up to natural light. That’s when the true colour reveals itself.
And if you find a piece that’s too beautiful to sit in a jar, that’s exactly what Mermaid Tears is for. Every piece of jewellery starts as a hand-hunted find, just like yours.
