Starphire is a brand of low-iron glass, not a different product. What varies between brands (almost nothing), and what actually matters on a shower door.
They are the same thing. Starphire is the brand name Vitro gives its low-iron glass, the way Kleenex is a brand of tissue; Guardian, Saint-Gobain, AGC and Pilkington each make an equivalent under their own names. For a shower door, what matters is that the glass is low-iron and tempered at 3/8 or 1/2 inch; which brand the fabricator cuts it from changes the edge tone by a shade you would have to hold two samples together to see. If you ask us for Starphire we will supply Starphire; if you ask for low-iron we will supply whichever low-iron our fabricator stocks, which in New York is usually Starphire anyway.
| Low-iron glass (generic) | Starphire® | |
|---|---|---|
| What it is | Float glass with the iron oxide reduced so it has no green cast | Vitro Architectural Glass’s brand of low-iron glass |
| Same product? | Yes — Starphire is one manufacturer’s low-iron glass | Yes — a brand name, not a different material |
| Other brands | Guardian UltraClear, Saint-Gobain Diamant, AGC Krystal Klear, Pilkington Optiwhite | — |
| Colour of the edge | Pale blue-white; brands differ very slightly in tone | Slightly azure edge; the tone many designers know |
| Light transmission (6 mm) | ~91% | ~91% |
| Thickness for a shower door | 3/8″ and 1/2″, tempered | 3/8″ and 1/2″, tempered |
| Availability | Every fabricator; from whichever float line they buy | Depends on the fabricator’s supplier; Vitro is US-made and widely stocked in the Northeast |
| Price | About the same across brands; 30–60% over standard clear | Same range |
| What to write on a quote | “Low-iron tempered” — any brand | “Starphire” if you want that specific brand |
Starphire was the first low-iron glass most American designers met, and it became the word people use for the category — on drawings, in showrooms, in searches. That is fine, except that it makes some owners think Starphire is a premium above low-iron, or that a quote for “low-iron” is a substitution. It is not. A fabricator who buys from Guardian will supply UltraClear and it will look the same in the bathroom. See low-iron vs standard clear for the comparison that actually changes the result.
Edge tone. Every low-iron glass has a faintly blue-white edge instead of green; the exact shade varies by maker by a small amount. Starphire runs slightly azure; some others run more neutral. Against white tile neither reads as a colour. Availability by thickness. All the majors make 3/8 and 1/2 inch; some brands are easier to get in 3/4 inch or in laminated form, which matters for railings and floors, not showers. What the fabricator stocks. Tempering is done locally, from stock the fabricator buys; the brand on your door is whichever float line they bought that month unless you specify. We specify when a customer asks and match to an existing panel when one is being replaced.
That it is low-iron at all, if the tile is white and the glass is thick — see 3/8 vs 1/2 inch. That it is tempered, which every shower door must be. That the edges are polished, because low-iron shows every edge. That the hardware is right for the weight and the wall behind it can carry it. And that a hydrophobic coating is applied before delivery, which does more for how the glass looks in year three than the brand does. Brand is the last item on that list.
Yes. Starphire is Vitro’s brand of low-iron glass. Guardian UltraClear, Saint-Gobain Diamant, AGC Krystal Klear and Pilkington Optiwhite are the same product from other makers.
Not in any way you would see in a bathroom. Edge tone differs by a shade between brands; transmission, clarity, thickness and price are the same.
“Low-iron tempered” gets you the product from whichever brand the fabricator stocks. Write “Starphire” only if you want that brand specifically, for example to match an existing panel.
They cost the same; both are roughly 30 to 60 percent above standard clear for the glass itself.
Yes, and other low-iron brands; in New York our fabricators most often stock Vitro Starphire.
Low-Iron vs Standard Clear Starphire Low-Iron Glass Frameless Shower Doors 3/8 vs 1/2 Inch Glass All Comparisons
About this page. Written by Alex GC Inc. d/b/a Alex Glass Construction and reviewed before publication by Aleksandr Chernovolenko, Managing Partner, with our design and estimating lead and a field foreman. Our foremen hold the NYC DOB Site Safety Training supervisor card and our crews the 40-hour worker card; we are certified to fabricate, install and service Alutech and Everest aluminum systems. Facts are drawn from our own projects, manufacturer test data and the applicable codes; where we are giving an opinion, we say so. Last reviewed September 2026. Credentials
Send a photo of the tile. We will say whether low-iron is worth it, which brand our fabricator has, and quote.
