Why Do Most Vintage Watches Use Acrylic Crystals?

When you think of vintage watches, you probably picture warm dials, aged lume, and domed glass that catches the light just right. But here’s a detail you might not have paid attention to — that “glass” is rarely glass at all. It’s actually acrylic, and it plays a huge role in the charm and wearability of vintage timepieces.

So why did so many classic watches use acrylic crystals? And why are they still loved by collectors today?

Acrylic — also known as Hesalite or plexiglass depending on the brand — is a lightweight, shatter-resistant plastic that was the go-to material for watch crystals from the 1940s through the 1980s. While modern watches often use sapphire or mineral glass, acrylic was the standard for decades, and for good reason.

First, it’s highly impact-resistant. Unlike glass, acrylic won't shatter if dropped or knocked. That made it perfect for tool watches, military watches, and sports watches — basically anything built to be used, not babied. It was cheaper and easier to mold, which also meant it could be produced in a wide variety of domed and curved shapes, giving vintage watches their signature warm, rounded look.

Then there’s the way it ages. Acrylic doesn’t just resist breaking — it develops character. Over time, it can pick up light scratches and scuffs, but these can be easily polished out with a dab of Polywatch or a light polish. And many collectors actually love the gentle softness and patina acrylic picks up — it’s part of the watch’s story.

You’ll also find acrylic on watches that went to space. Omega’s Speedmaster Professional — the “Moonwatch” — still uses an acrylic (Hesalite) crystal on its NASA-spec versions. Why? Because acrylic doesn’t shatter into dangerous shards in zero gravity.

In a world of ultra-hard, ultra-modern sapphire crystals, acrylic still offers something different: a slightly distorted edge at certain angles, a bit of warmth and glow in the light, and a tactile link to the past. It’s nostalgic, practical, and forgiving — just like the best vintage watches.

At Vintage Time London, we love acrylic for what it is — honest, usable, and full of charm. Most of our vintage pieces come with their original crystals, and where possible, we carefully polish them to preserve that vintage clarity and feel. And if yours is scratched or cloudy, we’re always happy to restore it.

So next time you see that soft dome catching the light on a vintage piece, know this — it’s not just plastic. It’s part of what makes your watch a time machine.