Laser Engraving Slate, Metal, Ceramic, and Glass: Materials Guide

Beyond wood and acrylic, your diode laser can engrave stone, ceramics, and glass with striking results.

Slate

One of the best materials for diode laser engraving. The laser vaporizes the surface creating permanent white contrast marks on dark stone.

Settings (20W diode):

• Speed: 2000–3000mm/min
• Power: 60–80%
• Lines/cm: 100–150
• Air assist: Off or very low

Tips:

• Clean thoroughly — oils affect quality
• Sand off any wax finish first
• A light coat of water helps keep surface cool
• For photographs, use Jarvis or Stucki dithering for best tonal range

Popular products: Coasters, trivets, house signs, memorial plaques.

Anodized Aluminum (Flat Stock)

No prep needed. Laser removes colored anodizing to reveal bare silver aluminum.

• Speed: 4000–6000mm/min
• Power: 30–50%
• Perfect for business card holders, guitar picks, tool labels

Raw Metal (Stainless Steel, Brass, Copper)

Diode lasers cannot ablate raw metal directly. You need laser marking spray (Cermark LMM-6000, Brilliance Laser Ink, or dry moly lube spray).

1. Clean with IPA — remove all oils
2. Apply thin, even coat of marking spray
3. Let dry completely (2–5 minutes)
4. Engrave: 800–1500mm/min, 80–100% power
5. Clean off residue with IPA to reveal permanent mark

The mark is embedded in the metal — dishwasher safe and scratch resistant.

Ceramic (Unglazed)

Terra cotta and raw bisqueware engrave well.

• Speed: 1500–2500mm/min, Power: 70–90%
• Glazed ceramic is inconsistent — the glaze reflects the laser. Test first.

Popular: Planting pots, decorative tiles, plant markers, garden stakes.

Glass

Glass is transparent and reflects IR, so you need to make the surface absorb the laser.

Wet paper method (best for diode lasers):

1. Wet newspaper or tissue paper
2. Press flat onto glass (no air bubbles)
3. Engrave through wet paper: 800–1200mm/min, 50–70% power
4. Remove paper, rinse glass

Result: Frosted etched appearance. Works on wine glasses (use rotary), picture frames, mirrors, glass tiles.

Warning: Tempered glass often shatters under thermal stress — never attempt.

Leather

Vegetable-tanned leather engraves with a beautiful burned, slightly embossed result.

• Speed: 4000mm/min, Power: 30–50%
• Safety: Use air assist and good ventilation. Chrome-tanned leather can produce toxic fumes.

Popular: Belts, wallets, keychains, notebook covers, guitar straps.

Quick Reference

Always test on scrap first — material composition varies significantly between manufacturers.