Perceived clarity
Perceived clarity — Both pass over 90 % of visible light on paper; the eye reads thickness instead. Glass carries iron and greens as it thickens, while cast acrylic stays near colourless at display thicknesses — on edge-lit designs the difference is not a spec line, it is the look.
How scratch behaves
How scratch behaves — Glass is hard, so scratches are fine and show as light refraction. Acrylic is soft, so scratches scatter white. Glass scratches are a will-you-notice question; acrylic scratches are a will-it-out question — which makes the daily wiping protocol opposite for the two materials.
| Seismic or tip-over risk display | acrylic by a distance — the failure mode differs too much |
|---|---|
| High-heat lighting on close range | glass does not creep toward the softening point; keep the distance honest |
| Handled and touched every day | acrylic can be polished back; glass re-polish costs approach new |
| Suspended or shelf-top weight limits | half the weight of glass at matched strength |
| Built-in display nobody swaps for a decade | that is glass's garden: surface hardness compounds over years |
What the spec table omits: the quality of ageing
Hardness numbers alone would give glass a clean sweep, and real display practice flips the verdict often. The split is what each material’s decay looks like. Glass decays as fine surface scratches accumulating until light scatters under spotlights. Acrylic decays coarsely and visibly — one bad week of paper towels shows. So glass is a material that ages slowly, and acrylic is one that stays young only under a followed protocol; the thing worth comparing is not the durometer but the shop’s weekly cleaning instructions.
Failure mode constrains the design
When glass fails, the display is a hazard, visitors are a hazard and the cleanup is overnight. When acrylic fails — unless the sheet is old and crazed — it crazes and whitens, and leaves time before it collapses. What a display designer actually specifies is not a transparent panel but what happens in the room when that panel reaches end of life; on insurance, visitors and night work, acrylic rewrites that part of the design significantly.
Practical selection: frequency decides, material follows
Convert the display question to frequencies and the choice gets fast. Swaps often — the opening mechanism is the real product and acrylic lightens it cheaply. Keep for a decade — glass’s hardness compounds and staff protocol drives ageing. Every move needs a transport crate — the weight gap becomes crate price. Choose on frequency; let the material be the consequence. That is how display shops actually decide.
Is display acrylic yellowing real or legend?
Real outdoors, largely legend indoors. Quality cast acrylic yellows so slowly in a lit interior that almost every 'yellowed' case report is really micro-scratch haze or trapped humidity fogging the inner face. Material defeat is reported more often than material actually loses.
What actually persuades glass-trained shops to switch?
Usually weight before hazard. Glass cases gain handlers at every move, lose floors at every install and gain straps at every inspection. What shops accept as the price of acrylic, consistently, is a written scratch protocol: which cloth, which fluid, how often the cloth changes — handed over with the case, not explained later at the first damage claim.