How many steps to polish granite?

Professionals use 7 steps for premium work: 50→100→200→400→800→1500→3000 grit, plus a buff step. A 5-step sequence works for medium-quality. The 3-step system (50/400/3000) is acceptable for production work but won't achieve maximum gloss on dark or high-mica granite.

Can I polish granite with an angle grinder?

Yes. You need a variable speed angle grinder (2,000-4,500 RPM) with a flexible rubber backer pad and 3-inch or 4-inch diamond resin pads. A fixed-speed grinder (10,000+ RPM) will glaze pads instantly and burn the stone.

What RPM should I use for granite polishing?

Coarse grits (50-200): 2,000-2,500 RPM. Medium grits (400-800): 2,500-3,500 RPM. Fine grits (1500): 3,000-4,000 RPM. Final polish (3000): 2,000-2,500 RPM. Buff: 1,500-1,800 RPM. Never exceed 4,500 RPM.

How long do diamond polishing pads last on granite?

A professional-grade 4-inch resin bond pad covers approximately 80-150 linear feet of edge polishing on granite. Coarse grits wear faster (80-120 ft); fine grits last longer (120-150 ft). Track pad usage by square footage, not time.

Granite Polishing Guide

Q: What grit should I start with for granite?

For new fabrication: start at 50# to remove saw marks, then follow the full 7-step sequence. For light restoration: start at 400#. For heavy restoration with deep scratches: start at 50# or 200#. Use the fingernail test to determine the starting grit.

How to polish granite countertops and slabs with diamond pads — from raw stone to mirror finish, step by step.

Factory-direct by KAIYI Diamond Pads Factory, Quanzhou, China

In This Guide

Understanding Granite Hardness & Composition
Choosing Diamond Pads for Granite
The 7-Step Grit Sequence
Dry vs Wet Polishing Granite
Edge Profiling & Polishing
How to Achieve a Mirror Finish
Restoring Old Granite Countertops
Common Problems & Fixes
Pro Fabricator's Workflow
3-Step vs 7-Step: Which to Choose
FAQ

1. Understanding Granite Hardness & Composition

Granite isn't a single material — it's a family of igneous rocks with varying mineral composition. This variation directly impacts how you polish it.

Granite Type	Mohs Hardness	Quartz Content	Polish Difficulty	Best Bond Type
Black Galaxy	6–7	Low	Moderate	Standard Resin
Absolute Black	6–7	Very Low	Easy	Standard Resin
Santa Cecilia	6–7	Medium	Moderate	Medium Bond Resin
Blue Pearl	7–8	High	Hard	Hard Bond Resin
Tan Brown	6–7	Medium	Moderate	Medium Bond Resin
White Granite (Alaska)	6–7	High	Hard	Hard Bond + White Resin

✦ Factory Insight: The sparkle in granite comes from mica minerals and quartz crystals. High-mica granites like Blue Pearl and Labradorite can gain 15–25% more visual depth when the full 7-step sequence is used. Skipping grits on high-mica stone is the #1 reason customers complain "it doesn't look like the showroom sample."

⚠ Common Pitfall: Treating all granite the same. Dark, low-quartz granite (Absolute Black) polishes quickly. High-quartz, light-colored granite (White Alaska) needs more time per grit and harder bond pads.

2. Choosing Diamond Pads for Granite

Bond Type Selection

Bond Type	Best For	Grit Range	Key Characteristic
Metal Bond	Heavy grinding, lippage removal, shaping	30–200	Most aggressive, longest life
Standard Resin Bond	Most granite countertops, edges	400–3000	Balanced cutting + polishing
Hard Bond Resin	High-quartz granite, Blue Pearl, white granite	400–3000	Wears slower on hard stone
White Resin Bond	Light-colored granite (no dye transfer)	400–3000	Dye-free formulation

→ Shop Granite Polishing Pads (3″ & 4″)

3. The 7-Step Grit Sequence for Granite

The professional standard for granite countertop polishing is the 7-step wet sequence. Each grit removes the scratch pattern left by the previous stage.

Step	Grit	Stage	RPM	Pressure	Result
1	50#	Grinding	2,000–2,500	15–20 lbs	Remove saw marks, flatten surface
2	100#	Grinding	2,000–2,500	15–20 lbs	Refine 50# scratch pattern
3	200#	Honing	2,500–3,000	12–18 lbs	Matte-smooth surface emerges
4	400#	Honing	2,500–3,500	12–15 lbs	Uniform matte finish
5	800#	Pre-Polish	2,500–3,500	10–15 lbs	Satin sheen appears
6	1500#	Polish	3,000–4,000	8–12 lbs	High sheen, scratches vanishing
7	3000#	Final Polish	2,000–2,500	5–10 lbs	Mirror finish, full clarity

✦ Pro Tip — The Fingernail Test: Run your fingernail across the surface. If it catches, start at 50#. If it glides but you feel texture, start at 200#. If it feels mostly smooth, start at 400#.

4. Dry vs Wet Polishing Granite

Factor	✅ Wet Polishing	⚠ Dry Polishing
Finish Quality	Superior gloss; full depth and sparkle visible	Lower gloss; risks heat marks and burn spots
Pad Life	80–150 linear feet on granite edges (4″ pad)	~40–70% of wet pad life
Dust	Slurry (contained mess)	⚠ Airborne silica dust — requires HEPA + respirator
Best Use	Shop fabrication, indoor work, all finishing stages	On-site quick fixes where water isn't available

5. Edge Profiling & Polishing Granite Countertops

Profile	Tooling Strategy	Difficulty
Eased Edge	Start at 200#, light touch, 5-min total for 8 ft edge	Easy
Bullnose	Profile with diamond router bit first, then polish 200#–3000#	Moderate
Ogee	Router bit for shape, then 3″ pads for curves	Hard
Mitered Waterfall	Polish miter face before assembly; light touch-up after glue-up	Moderate–Hard

6. How to Achieve a Mirror Finish on Granite

Complete the full 7-step sequence — no skipping
Drop RPM for the 3000# stage — 2,000–2,500 RPM maximum
Lighten pressure progressively — 5–8 lbs at 3000#
Use a dedicated buff pad — after 3000#, clean felt buff at 1,500–1,800 RPM
Final wipe with acetone — inspect under raking light from multiple angles

✦ Factory Data: On Black Galaxy granite, the full 7-step + buff sequence achieves 92–96 GU vs 78–85 GU for a 3-step system. That 10–15 GU difference is visible to the naked eye.

7. Restoring Old Granite Countertops

Condition	Starting Grit	Full Sequence	Est. Time (50 sq ft)
Minor wear, dull spots	400#	400→800→1500→3000→Buff	2–3 hours
Visible scratches throughout	200#	200→400→800→1500→3000→Buff	3–5 hours
Heavy damage, deep scratches	50#	Full 7-step: 50→100→200→400→800→1500→3000→Buff	5–8 hours

8. Common Granite Polishing Problems & Fixes

🟡 Granite Not Shiny After Polishing

Cause: Skipped grits, insufficient time per grit, or pad glazing.

Fix: Drop back 2 grit stages and re-polish. Always verify with raking light before advancing.

🟡 Swirl Marks / Circular Scratches

Cause: Inconsistent pad movement — changing direction mid-grit.

Fix: Drop back to 400# and re-polish with straight-line passes. Overlap each pass by 50%.

🟡 Burn Marks / Black Spots on Granite

Cause: Overheating — insufficient water flow, too much pressure, or too high RPM at fine grits.

Fix: Back up to 200# and re-polish with full water flow. Never exceed 2,500 RPM at 3000#.

🟡 Haze / Cloudiness After Sealing

Cause: Sealer applied over an improperly polished surface.

Fix: Strip the sealer, then re-polish from 400# through 3000#. Do the raking light check on the dry, unsealed surface before applying sealer.

🟡 Pad Glazing

Cause: Resin bond melted from excessive heat or pressure.

Fix: Dress the pad by running it over scrap granite or 60-grit sandpaper. Prevent by reducing pressure and increasing water flow.

9. Pro Fabricator's Granite Polishing Workflow

Complete 12-step workflow from slab to showroom-ready granite countertop.

#	Step	Details	Tool
1	Inspect slab	Check for natural fissures, resin fills, or doctored areas.	Flashlight + marker
2	Template & cut	CNC or bridge saw. Leave 1/16″ extra for edge profiling.	Bridge saw / CNC
3	Edge profile	Shape the edge profile with a diamond router bit.	Router + profile bit
4–10	Polish 50#→3000#	Full 7-step wet sequence. Raking light check between each grit.	4″ resin pads + VS grinder
11	Buff	Clean buff pad at 1,500–1,800 RPM. 10–15 sec per linear foot.	Felt buff pad
12	Seal	Clean with acetone. Apply impregnating sealer. Cure 24 hrs.	Lint-free cloth + sealer

→ Shop Full 7-Step Granite Pad Set (50#–3000#)

10. 3-Step vs 7-Step: Which Polishing System to Choose

Factor	3-Step System (50/400/3000)	7-Step System (50–3000)
Time	Fast — 30–45 min per 50 sq ft	Thorough — 1.5–2.5 hrs per 50 sq ft
Gloss (GU)	78–85 GU on Black Galaxy	92–96 GU on Black Galaxy
Best For	Production work, rental properties, concrete floors	🔥 Premium countertops, high-end residential, dark granite

11. FAQ — Granite Polishing Questions from Fabricators

What's the best diamond pad for polishing granite?

Wet resin bond diamond pads, 4-inch diameter, in a full 7-step set (50#–3000#) with a flexible rubber backer pad. For high-quartz granites, switch to hard bond resin pads.

What grit should I start with for granite?

For new fabrication: start at 50#. For light restoration: start at 400#. For heavy restoration: start at 50#. Use the fingernail test to decide.

Why does my granite look hazy after polishing?

Haze is almost always caused by skipped grits. Fix: drop back 2 grit stages and re-polish without skipping. Other causes: pad glazing, hard water residue, or polishing over uncleaned slurry.