In natural stone, quality is sought not only in appearance but in measurable values. For every batch Petrova has physical and mechanical properties tested in independent laboratories and gives the results to the customer.
Standards applied
- TS EN 1469: Natural stone – slabs for cladding
- TS EN 12058: Natural stone slabs for floors and stairs
- TS EN 1341/1343: External paving
- TS EN 1936: Determination of density and water absorption
- TS EN 1926: Compressive strength
- TS EN 12371: Frost resistance
- TS EN 14231: Slip resistance (pendulum test)
Certificates
ISO 9001 quality and ISO 14001 environmental management certificates, the CE marking (declaration of performance) and quarry operating licences are in the documents section. For every shipment an origin certificate, test report and packing list are prepared.
Grades
Slabs are offered in grades A (export), B (standard) and C (economy). In grade A vein continuity, colour matching and surface defect rate are controlled to the tightest tolerance; the grading is stated with sample photos in the quote.
Laboratory and monitoring
The in-house laboratory at our plant measures water absorption, density and surface gloss on samples taken randomly from each batch, while mechanical tests are carried out in accredited external laboratories. Results are stored in a database by block number and shared with the buyer on request.