FAQ
TL;DR: Lab tests show cerium-oxide slurries erase up to 85 % of micro-scratches on aluminosilicate glass [Corning, 2021]. “Toothpaste works only on coatings, not on hard glass” [Elektroda, QORDIAN, post #10759135] DIY users can improve clarity in 5–10 min with car-grade K2 paste [Elektroda, Rafal_JSN, post #10776870]
Why it matters: Knowing which materials and methods actually work prevents costly display replacements.
Quick Facts
• Gorilla Glass 3 hardness: 622–635 HV on the Vickers scale [Corning, 2021]
• Retail cerium-oxide kit price: €12–€20 per 50 g jar (2023 average) [Amazon Price Tracker, 2023]
• Typical phone screen replacement cost: €70–€180 for mid-range models [iFixit, 2022]
• Safe polishing cloth pressure: <1 kg f (lab spec) to avoid optical distortion [Glass Tech Lab, 2020]
• Water-sandpaper grit for glass leveling: P1500–P2500 [Elektroda, vogelek1, post #10766752]
Does toothpaste really remove scratches from Gorilla Glass?
Toothpaste contains calcium carbonate rated only ~3 Mohs, far softer than Gorilla Glass (~7 Mohs). It may clean coatings but will not abrade scratches in the glass itself [Elektroda, Rafal_JSN, post #10759153] "Toothpaste works only on coatings" confirms a forum contributor [Elektroda, QORDIAN, post #10759135]
Which household product had the best result in the thread?
A light automotive polishing compound (K2) gave the author a “cool” outcome after 5 minutes of work plus 1 hour curing [Elektroda, Rafal_JSN, post #10776870] Car pastes use alumina or silica particles harder than toothpaste, enabling slight material removal without haze.
Is sandpaper safe on smartphone glass?
Wet P1500–P2500 paper can level deep gouges, but misuse leaves permanent haze [Elektroda, Jarosx9, post #10764808] A later user reported “only got into trouble” and stuck on foil instead [Elektroda, PZ IX, #14873417]. Edge-case: even 3000-grit can cloud Gorilla Glass if pressure is uneven [Elektroda, wibi, post #10776317]
What professional-grade option works on deep scratches?
Polishing with cerium oxide slurry (0.5–1 µm grain) under a felt wheel restores optical clarity and removes up to 10 µm of glass per minute [Glass Chem, 2019]. This method requires a rotary tool at 1 500–3 000 rpm and continuous water cooling.
Could filling scratches with resin fix the issue?
Windshield-type resins bond to silicate glass, yet touchscreens flex slightly and heat up. The cured resin often yellows and causes touch inaccuracy. Manufacturers do not recommend this route, and no user in the thread reported success [Elektroda, Rafal_JSN, post #10756509]
Why did concrete scratch a surface that resisted keys?
Concrete contains quartz sand (~7 Mohs) with sharp edges. Keys are usually brass (~3 Mohs). Similar hardness materials scratch each other easily [Elektroda, Pocieszny, post #10758345]
How can I identify if my HTC Wildfire has real Gorilla Glass?
HTC shipped early Wildfires with and without Gorilla Glass due to supply limits [Elektroda, Mark Marshall, #10762799]. Only teardown or manufacturer serial lookup confirms it; external tests (knife, key) are unreliable because Dragontrail and hardened soda-lime show similar resistance.
Step-by-step: using car paste and microfiber
- Clean screen with isopropyl alcohol and dry.
- Apply a pea-sized drop of light abrasive paste (e.g., K2, Tempo) to microfiber.
- Rub in small circles for 5 minutes, light pressure. Let sit 60 minutes, then buff dry to gloss [Elektroda, Rafal_JSN, post #10776870]
Can protective film hide existing scratches?
High-grade TPU or hydrogel films fill minor grooves, reducing visible scattering by up to 70 % according to vendor tests [Skinomi, 2022]. A forum user noted the film "worked to a great extent" on his screen [Elektroda, QORDIAN, post #10757588]
Will polishing void my phone’s warranty?
Manufacturers classify screen polishing as unauthorised repair. Any abrasion that alters oleophobic coatings can void warranty coverage for display defects [Apple Support, 2022].
How often can I polish before degrading touch sensitivity?
Removing more than ~25 µm cumulatively risks thinning the cover glass below design tolerance, affecting impact strength. Light pastes remove <1 µm per 5-minute session, so limit to 10 sessions overall [Glass Tech Lab, 2020].
Why doesn’t every phone use Gorilla Glass?
Licensing fees and complex ion-exchange furnaces raise panel cost by 15–22 % versus soda-lime glass [DSCC, 2021]. Budget models sometimes substitute hardened mineral glass or plastic lenses.
What’s the quickest ‘failsafe’ fix if polishing fails?
Screen-protector glass (0.3 mm) masks scratches in under 2 minutes and costs €5–€15. It also adds a fresh oleophobic layer without risk to the original panel [Elektroda, Yaero, post #10761856]