A Guide to Button Materials
Curated Buttons was built with sustainability in mind. I searched for natural materials, deadstock, forgotten inventories of long-gone stores. When I started, I had never even heard of corozo or casein. My search led me to button makers in France, Italy, the U.K., Germany and China.
I've also found incredible buttons second-hand - unused, but already with a history. Many of these are metal and plastic - timeless.
I've supplemented natural material buttons with some new plastic and resin buttons, offering much needed colour and lightness to the collection.
Corozo (Tagua Nut)
What it is: Corozo buttons are made from the nut of the tagua palm, which grows in the equatorial rainforests of South America – primarily Ecuador, Colombia, Panama, and Peru. You'll sometimes see them called "vegetable ivory" – and once you've held one, you'll understand why. The material is dense, smooth, and has a lustre remarkably similar to animal ivory.
The lifecycle: Here's what makes corozo extraordinary: it takes up to 15 years for a tagua palm to mature from germination to first crop. But once mature, that tree can produce nuts for up to 100 years. Each year, a single palm yields 15-20 kg of tagua –enough for thousands of buttons.
The nuts grow in large, spiny clusters called "mococha." And here's the key: they fall to the ground naturally when ripe. No cutting, no harvesting from the tree. The palm lives on, undisturbed, producing year after year. Corozo buttons don't just grow on trees – they fall from them.
How they're made: Once collected, tagua nuts are dried until the interior hardens completely. The dried nuts are then sliced, shaped on lathes, drilled, and polished. Because each nut has natural colour variations – from creamy white to warm tan – no two buttons are exactly alike. Corozo takes dye beautifully, producing rich, saturated colours that synthetic materials can't match.
Why you'll love them: Corozo has a satisfying weight and subtle natural grain. It's hardwearing, scratch-resistant, and heat-resistant (safe for ironing and steaming). Because tagua is so economically valuable, it gives rainforest communities a reason to protect the forest rather than cut it down. When you choose corozo, you're helping preserve ancient rainforest.
Care: Machine washable, steam-safe, dry-clean safe. Avoid prolonged soaking (24 hours or more).
Horn
What it is: Horn buttons are made from water buffalo or ox horn – a byproduct of the farming industry, primarily sourced from India, which has a thriving horn button industry supported by its large cattle population. Livestock isn't raised for their horn; the material comes from animals already in the food system. For the small, subsistence farmers who raise these cattle, selling horn provides vital additional income.
A bit of history: Horn has been used for buttons for centuries, with processed horn buttons patented as early as 1830. Industrial production grew significantly through the 19th century, and horn quickly became a luxury material adopted by fine tailors and fashion houses worldwide.
How they're made: Horn is made of keratin – the same protein as human hair and nails – which means it's fully biodegradable. The raw horn is a hollow cone that tapers to a solid tip. The tips are removed and can become toggles or round button blanks. The hollow sections are softened with heat and moisture, then pressed flat into "plate" horn, from which blanks of various sizes are cut, shaped, drilled, and polished.
Because the grain structure runs lengthwise, the appearance of each button varies depending on where it was cut. Colours range from deep black through browns, ambers, and creamy whites. Manufacturers sort buttons to minimize variation within batches, but differences are normal and part of the material's character.
Why you'll love them: Horn has an organic warmth that plastic can't replicate. It's strong, lightweight for its size, and develops a gentle patina over time. The natural patterning means each button is genuinely unique – a subtle detail that elevates handmade garments.
Care: Horn is sensitive to prolonged moisture. Hand washing or dry cleaning is ideal; avoid tumble drying on high heat.
Casein
What it is: Casein buttons are made from milk protein – the same casein that forms when milk curdles into cheese. Invented in Germany in the late 1890s and commercialized at the Paris Exhibition in 1900, casein plastic (often called "galalith," from the Greek for "milk stone") became a staple of button-making through the mid-20th century. In the UK, it was marketed as "Erinoid" from 1914. Production largely ceased in the 1970s when polyester displaced it, but a small number of specialist manufacturers have revived this heritage material.
How they're made: The process begins much like cheesemaking: rennet (a naturally occurring enzyme) separates milk into curds and whey. The casein is then hardened into sheets or rods through a slow curing process that can take weeks or months depending on thickness. The leftover whey is sold commercially, so nothing goes to waste.
Once cured, the material is cut, shaped, dyed, and polished. Casein can be produced in solid colours, pearlescent finishes (an alternative to mother-of-pearl), or patterns that mimic natural horn. The depth and clarity of colour is exceptional – historically, casein was prized for its ability to be dyed in ways other materials couldn't match.
Why you'll love them: Casein has a distinctive feel – slightly warmer to the touch than polyester, with a richness that reads as quality. Unlike the plastic buttons that replaced it, casein is biodegradable and sustainable. Modern casein buttons are robust, hard-wearing, and hold up well to machine washing – a significant improvement over historical versions, which were more moisture-sensitive.
Care: Modern casein buttons are designed for everyday use and machine washable.
Mother of Pearl (Shell)
What it is: Mother-of-pearl buttons are cut from nacre – the shimmering inner layer of mollusk shells. This is the same substance that coats pearls, which explains the characteristic luminosity. Different shells produce different effects: oyster, abalone, mussel, and freshwater mollusk each have their own colour range and patterning.
A bit of history: People have been making shell buttons since medieval times, but the 19th century was the golden age. England developed a major industry – London alone had over 200 button factories by the 1890s, with thousands more workers in Birmingham. Across the Atlantic, a German immigrant named John Boepple noticed that a bend in the Mississippi River near Muscatine, Iowa had created ideal mussel beds. The American freshwater pearl button industry exploded from there, and by 1905 Muscatine was turning out well over a billion buttons a year. (The waste shells piled up so high they were crushed and used as road paving.) Over-harvesting eventually depleted the river beds, and plastic took over mid-century. Modern production has largely shifted to Asia, with growing emphasis on sustainably farmed shells.
How they're made: Turning raw shell into a finished button is painstaking work – traditional methods involve close to twenty steps including cutting, grinding, polishing, dyeing, drilling, and sometimes hand-carving decorative patterns. Skilled work is needed at each stage to preserve the shell's natural light-catching properties. Because every shell is different, every button is different too – colours range from cool white through pink and blue to full rainbow iridescence.
Why you'll love them: Nothing else catches light quite the way nacre does. The shimmer shifts as you move, and that quality simply cannot be manufactured synthetically. Shell is also surprisingly tough – after all, its natural purpose is armour for the creature inside.
Care: Keep acidic cleaners away from mother of pearl; acids break down calcium carbonate and will dull the surface over time. Hand washing is safer than machine washing, which risks chips and cracks.
How to spot the real thing: Real shell feels noticeably cool against your skin – try pressing it to your cheek. Genuine buttons often have a smooth polished front but a rougher, unfinished back; imitations tend to look uniform on both sides. The classic test: run it lightly across your teeth. Real nacre has a subtle grit to it; plastic glides smooth.
