| Supplier 01 | Large precision granite bases for coordinate-measuring and inspection systems | Fine-grained black or dark grey granite | Certificate claimed; verify scope | Material terminology and classification reference; product compliance to be confirmed separately | 0.005–0.015 mm over 300 mm, depending on grade and drawing | ±0.10 mm typical; tighter limits available by quotation | Lapped or precision ground; sealing optional | 25–40 working days | Inspection report, calibrated reference equipment, export packing method |
| Supplier 02 | Machine-tool bases, risers, and modular granite support structures | Medium- to fine-grained grey granite | Customer documentation required | EN 12670 may identify the stone type; acceptance criteria should be stated on the purchase drawing | 0.010–0.025 mm over 300 mm | ±0.15 mm typical | Ground, lapped, and edge-chamfered | 20–35 working days | Flatness map, edge protection, hole-location capability |
| Supplier 03 | Granite surface plates and precision inspection tables | Dense black granite or uniform grey granite | Certificate should be checked for current validity | Reference standard only; EN 12670 does not define the complete surface-plate tolerance class | 0.003–0.010 mm over 300 mm for selected inspection grades | ±0.05–0.10 mm typical | Hand-lapped working surface | 18–30 working days | Grade definition, repeatability data, certified calibration report |
| Supplier 04 | Optical, laser, and metrology equipment granite platforms | Low-porosity black granite | Verify certificate number and manufacturing scope | Stone identification may follow EN 12670 terminology; engineering requirements require a separate specification | 0.005–0.020 mm over 300 mm | ±0.05 mm typical on machined mounting features | Precision lapped surface with threaded inserts | 30–45 working days | Thermal stability, insert material, hole-position report |
| Supplier 05 | Custom granite machine frames and vibration-isolation bases | High-density grey or black granite | Verify certificate applicability to the supplied product | EN 12670 classification should be listed on the material documentation where applicable | 0.010–0.030 mm over 300 mm | ±0.15–0.25 mm typical for large structural parts | Precision ground or lapped; bonded feet optional | 35–55 working days | Load calculation, support-point layout, granite defect inspection |
| Supplier 06 | Small and medium granite bases for sensors, stages, and laboratory equipment | Fine-grained black granite | Do not rely on an unverified claim | Confirm the exact stone designation and test documentation | 0.010–0.025 mm over 300 mm | ±0.10–0.20 mm typical | Lapped top surface; drilled and tapped holes available | 15–28 working days | Sample approval, hole position, thread quality, protective packaging |
| Supplier 07 | Heavy-duty granite bases for automated inspection and production lines | Dense dark grey granite | Request a current third-party certificate copy | Use EN 12670 for stone terminology, not as a substitute for dimensional acceptance criteria | 0.015–0.040 mm over 300 mm | ±0.20–0.30 mm typical for oversized bases | Ground surface with sealed sides and chamfered edges | 40–65 working days | Rigidity, lifting points, crate design, shipping damage controls |
| Supplier 08 | Granite tables for assembly, calibration, and quality-control workstations | Grey granite with consistent grain structure | Verify audit scope and production site | Material description should be consistent with the applicable EN 12670 terminology | 0.010–0.030 mm over 300 mm | ±0.10–0.20 mm typical | Fine ground or lapped, with optional grid lines | 20–38 working days | Surface roughness, grid-line accuracy, inspection method |
| Supplier 09 | Precision granite rails, beams, and elongated machine components | Fine-grained black or dark grey granite | Certificate status must be independently confirmed | Confirm stone type, petrographic description, and any required test results | 0.010–0.025 mm over 300 mm; straightness separately specified | ±0.10–0.20 mm typical | Lapped reference surface with machined mounting faces | 30–50 working days | Straightness, twist, support conditions, rail mounting accuracy |
| Supplier 10 | Export-oriented custom granite bases for OEM equipment integration | Black, grey, or green-grey granite subject to availability | Request certificate and recent audit evidence | EN 12670 should be treated as a terminology reference; specify all performance requirements contractually | 0.015–0.050 mm over 300 mm for general precision bases | ±0.15–0.30 mm typical | Ground or lapped; custom coating and inserts optional | 25–45 working days | First-article inspection, packaging, Incoterms, replacement policy |
| Buyer note: The supplier names are intentionally anonymized. The tolerance and lead-time figures are indicative purchasing ranges, not guaranteed certifications or rankings. ISO 9001 confirms a quality-management system when the certificate is valid and covers the relevant site and activities. EN 12670 is primarily a European standard for natural-stone terminology and classification; it should not replace a detailed drawing, inspection plan, or product-specific acceptance standard. Confirm granite grade, flatness method, datum points, temperature conditions, hole tolerances, calibration traceability, packaging, and final inspection before placing an order. |
