Quality Control
Zero Compromise on Quality
ISO 9001:2015 certified. Every shipment passes a 5-stage inspection process before it leaves our factory.
Our Quality Philosophy
Our Quality Philosophy
At Kingstone, quality is not a department — it is a culture embedded at every stage of production. From the moment a raw block enters our yard to the moment a container is sealed, our QC team monitors, measures and documents every critical parameter.
We operate under ISO 9001:2015 and follow EN 1341, EN 1342 and EN 1343 European standards for natural stone paving products, as well as ASTM C615 and C503 for granite and marble respectively. Third-party inspection by SGS or Bureau Veritas is available on request.
5-Stage Quality Control Process
5-Stage Quality Control Process
Raw Material Inspection
Every incoming block is inspected for colour consistency, structural soundness, absence of cracks, fissures and inclusions. Blocks that do not meet our grading criteria are rejected before entering production.
In-Process Dimensional Check
After cutting, 100% of pieces are measured with digital callipers and laser gauges. Thickness, length and width are verified against the order specification. Tolerance: ±1 mm standard, ±0.5 mm precision grade.
Surface & Finish Inspection
Polished pieces are checked for gloss level (≥80 GU for standard polish), surface flatness and absence of scratches, pits or tool marks. Flamed and bush-hammered pieces are checked for texture uniformity.
Colour & Pattern Matching
Each batch is compared against the approved sample under standardised D65 lighting. Colour deviation is assessed visually and, for critical orders, with a spectrophotometer. Pieces outside tolerance are segregated.
Pre-shipment Final Inspection
Before packing, a final inspection team checks quantity, dimensions, surface quality and packing integrity. A photographic inspection report is issued for every shipment. Third-party inspection available on request.
Standards & Certifications
Standards & Certifications
Physical Property Testing
Physical Property Testing
Our Quality Guarantee
Our Quality Guarantee
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