What Is Engineered Stone?
Engineered stone — also known as a "quartz surface" — is an artificial surface product made in an industrial process:
- Content: 90-93% quartz + 7-10% polyester resin + pigment + decorative elements (glass, metal particles)
- Production: the granitic mix is vacuum-pressed → then cured (vibro-compression)
- Example brands: Caesarstone, Silestone, Quartzform, Cosentino, Belenco, Oltastone (Türkiye)
- Mohs hardness: ~7 (close to granite, because quartz dominates)
- Slab size: on average 3050 × 1400 mm or 3200 × 1600 mm (fixed by the manufacturer)
How It Differs from Natural Stone
Natural Stone (Marble / Granite)
- Of natural origin, with colour and pattern varying block by block
- Mohs 3-5 (marble) / 6-7 (granite)
- Porous — affected by what is spilled on it (lemon, vinegar and so on)
- Care: annual buffing recommended
- There can be a colour difference within a single slab
Engineered Stone
- Industrial — consistent colour, pattern and quality
- Mohs ~7 — a hardness close to granite
- Non-porous thanks to the resin (does not absorb or stain)
- Minimal care — daily cleaning is enough
- Slab consistency — pieces are joined side by side and the difference is invisible
- A 10-15 year manufacturer warranty is common
CNC Machining Characteristics
Engineered stone is as hard as granite, but because of its resin content heat control during cutting is critical. Too much heat melts the resin and deforms the surface.
| Parameter | Marble | Granite | Engineered Stone |
|---|---|---|---|
| Mohs hardness | 3-5 | 6-7 | ~7 |
| Blade mesh | #50-60 | #40-50 | #60-80 (finer) |
| Bond hardness | Soft to medium | Medium to hard | Medium |
| Cutting speed | 1,500-2,500 mm/min | 500-1,500 mm/min | 800-1,800 mm/min |
| Cooling flow | 20-30 L/min | 30-45 L/min | 35-50 L/min (CRITICAL) |
| Cutting depth per pass | 50-100 mm | 30-60 mm | 40-70 mm |
| Blade life (linear) | 300-500 m | 80-150 m | 150-250 m |
Cooling Is Critical
If cooling is inadequate on engineered stone the resin melts and leaves a "burn" mark on the surface. It needs 30-40% more water flow than granite cutting. Dry cutting is NEVER done.
Blade Selection — For Engineered Stone
- Mesh: #60-80 (finer than the #40-50 typical for granite)
- Bond: medium hardness (the hard bond used for granite is too much for engineered stone)
- Segment height: 8-10 mm
- Segment count: 20-28 (more than for granite — to spread the heat)
- Blades labelled "for engineered stone" should be preferred — choose a part certified by the manufacturer for engineered stone
- Using a standard granite blade on engineered stone: tool life falls by 30-40% and the surface deforms
Polishing and Surface Quality
The polishing process when working engineered stone differs from natural stone:
- Stage 1: 60 grit (the rough pass)
- Stage 2: 100 grit
- Stage 3: 200 grit
- Stage 4: 400 grit
- Stage 5: 800 grit
- Stage 6: 1500 grit
- Stage 7: 3000 grit (or polishing powder)
- Final: a buffing powder made for engineered stone (manufacturer-approved)
One or two more stages are added compared with natural stone polishing — to reach the "mirror" gloss of the engineered surface.
Polishing Tip
Using polishing products approved by the manufacturer (Caesarstone, Silestone and so on) keeps the warranty conditions intact. Using unapproved polishing products can reduce the 10-15 year manufacturer warranty.
Edge Profiles
- Plain / eased — the most common, a modern look
- Bullnose (a half-round) — premium, popular in the past
- Ogee — a classic widely used in Europe
- V-cut (mitred) — jointed at the corner for a thick appearance (60-80 mm of visible thickness)
- Eased + bevel — a soft corner + a 45° chamfer
- Every profile in a single setup with a 5 axis machine
The Sink Cut-Out — Special Care
The internal corner radius is critical on engineered stone — a sharp corner (R<10 mm) can develop micro-cracks over time. Manufacturers generally recommend a minimum internal corner radius of 25 mm.
- The internal edge of the sink cut-out: a minimum of R25 mm
- Softening the corners with a radius — a sharp corner is forbidden
- An internal corner on an outer edge: a minimum of R15 mm
- The manufacturer's cutting guide must be followed
- The pierce (entry) point — in a corner that will not be seen
Engineered Stone Manufacturer Warranties
- A standard 10-15 year manufacturer warranty (on kitchen countertop applications)
- Warranty condition: a manufacturer-approved fabricator (the workshop must be certified)
- Manufacturer-approved polishing products must be used
- Specified edge profiles + internal corner radius standards
- As the workshop, a 12-month warranty against production faults for the customer (on top of the manufacturer warranty)
- Passing on the warranty: the certificate must be given to the customer and specifically noted on the invoice
Workshop Productivity Comparison
| Process | Marble | Granite | Engineered Stone |
|---|---|---|---|
| Cutting time (m²) | Fast | Medium | Medium |
| Polishing stages | 6-7 | 7-9 | 7-8 |
| Blade cost (relative) | Low | High | Medium |
| Risk of customer complaint | Medium (tone variation) | Low (hard) | Low (consistent) |
| Manufacturer warranty | — | — | 10-15 years (transferable) |
| Customer preference (modern segment) | Traditional | Classic | Modern + premium |
Market Trend
Engineered stone has grown by 200%+ in Türkiye over the past ten years. The modern and premium segment plus apartment projects are the main drivers. In the European market its share has reached 40%+; in Türkiye it is still 15-20%, but rising fast.
Workshop Strategy
Workshops that build competence in engineered stone machining reach the modern customer segment. Being manufacturer-certified (Caesarstone Trade Partner, Silestone Authorized Fabricator and the like) is valuable for market position.