| Water Absorption | ASTM C97/C97M; EN 13755 | Independent laboratory test report identifying the stone type, sample, method, and test date | Water absorption by mass, specimen condition, laboratory identity, and reported uncertainty where available | Compare the result with the project specification; neither standard establishes one universal acceptance limit for every application |
| Bulk Specific Gravity | ASTM C97/C97M | Test report with calculation details and specimen identification | Bulk specific gravity, dry mass, saturated mass, submerged mass, and number of specimens | Confirm consistency with the approved technical data sheet and the specified stone selection |
| Test Method Compliance | ASTM C97/C97M or EN 13755, as specified by the contract | Full laboratory report rather than a marketing data sheet alone | Standard edition, test procedure, sample preparation, conditioning time, and signatory approval | Do not combine results from different methods without documenting the method difference |
| Quality Management System | ISO 9001:2015 | Valid ISO 9001 certificate issued by an accredited certification body | Certificate number, legal entity, certified scope, issue date, expiry date, and certification body | Verify certificate validity and scope; ISO 9001 certification does not certify stone performance by itself |
| Quarry and Material Traceability | Buyer specification; project quality plan | Quarry location, extraction authorization, block identification, and production batch records | Source location, block number, lot number, extraction date, and link to finished slabs or tiles | Require traceability from quarry block through fabrication, packing, and shipment |
| Dimensional Accuracy | Purchase specification; applicable product standard | Dimensional inspection report and approved shop drawings where applicable | Length, width, thickness, squareness, edge condition, flatness, and calibrated measuring equipment | Use contract tolerances; record inspection results by lot or shipment |
| Appearance and Color Control | Approved reference sample; architectural specification | Approved physical sample, high-resolution slab photographs, and lot approval record | Veining, background tone, fissures, resin treatment, repairs, surface finish, and acceptable natural variation | Approve variation limits before production; natural stone is not expected to be visually identical piece to piece |
| Surface Finish | Project finish schedule; applicable slip-resistance requirements | Finish sample, process description, and inspection record | Polished, honed, leathered, flamed, or other specified finish; gloss, texture, scratches, pinholes, and edge treatment | Match the approved control sample and confirm suitability for the intended interior or exterior use |
| Packaging and Export Readiness | Incoterms® rule; destination import requirements | Packing specification, commercial invoice, packing list, origin documentation, and shipping photographs | Crate material, moisture protection, slab support, gross weight, package marks, container loading plan, and HS classification | Approve packaging before dispatch and confirm compliance with destination customs and wood-packaging rules |
| Nonconformance and Claims Control | ISO 9001:2015 quality-process principles; purchase contract | Nonconformance procedure, corrective-action record, and warranty or claims process | Response time, evidence requirements, replacement or credit terms, root-cause analysis, and corrective-action closure | Include measurable claim deadlines and inspection procedures in the purchase agreement |