A natural stone sample approval should record a decision that production teams can use: which material, which finish, which range of variation and which part of the project has been accepted. A small marble sample is useful for choosing a direction, but it cannot show every vein or the appearance of a completed room.
This checklist helps architects turn an attractive sample into a traceable approval package. For the wider material-selection process, start with our Natural Stone Specification Guide for Architects.
1. State what the submission is intended to approve
Give each submission one clear purpose. An early colour reference, a production finish sample, a range set and an installed mock-up answer different questions. Avoid an unqualified “approved” stamp that could be interpreted as acceptance of all four.
- Concept sample: establishes the proposed material family and design direction.
- Finish sample: records the appearance and feel of a particular treatment on the proposed stone.
- Range set: shows the accepted spread of colour, veining and other visible characteristics.
- Installed mock-up: demonstrates selected details in an assembly, including joints and adjacent materials.
Swenson Stone Consultants explains the distinction between small samples, representative range sets and mock-up panels in its guide to evaluating stone samples. The review process below develops that distinction into a practical project record.
2. Identify the material behind the sample
Ask the supplier to label the submission with the commercial name, source reference, finish, thickness and date. Record whether it represents a general reference or material currently proposed for the project. Add block, batch or slab identifiers when these are available and relevant.
For example, an Afyon White marble sample can help establish the palette. The eventual production submission still needs to identify the supplied selection and finish. A product name alone does not document those decisions.
3. Review a range instead of choosing one perfect piece
Ask for enough representative pieces to discuss the variations that matter to the design. These may include background tone, vein intensity, contrasting inclusions and the appearance of any disclosed filling or resin treatment. Record accepted characteristics with photographs and written notes; keep the physical references too.
A narrow visual selection can affect available yield and cost. Discuss that trade-off before the material is ordered. Digital Dry Layout’s range-to-sign-off guidance describes the relationship between selection, cutting layout and visual approval. Do not turn a supplier’s example yield into a guaranteed project allowance.
4. Check the finish under the proposed lighting
Review samples beside the actual adjacent finishes wherever possible. Use the intended orientation: a floor sample viewed horizontally does not answer every question about a vertical wall. Note the light source and viewing position in the approval record so later comparisons are meaningful.
Where appearance after wetting is relevant, agree a suitable comparison with the supplier. Keep visual review separate from slip performance, water management and other technical requirements. A finish that looks acceptable has not thereby passed a performance assessment.
5. Match the mock-up to the unresolved decision
Specify the features that need to be demonstrated rather than choosing an arbitrary mock-up size. A wall return may need a corner, reveal and joint. A floor transition may need the stone, adjoining material and finished-level relationship. A mosaic may need several sheets, an edge condition and the proposed grout.
Ask Architectural Studio’s sample and mock-up guidance highlights reviewing materials in their intended context. On your project, document which details the mock-up actually includes and which remain unresolved.
6. Keep visual approval separate from technical release
Use a separate review line for technical documents and installation coordination. Depending on the application, the package may need current material test reports, substrate requirements, fixing details, waterproofing compatibility or specialist design review. The relevant project professionals determine the requirements.
A signed colour range is not permission to fabricate an unreviewed anchor detail. Likewise, acceptance of a drawing does not establish that a different production batch falls within the agreed visual range.
7. Use a clear approval record
The following fields form an editorially proposed checklist that a project team can adapt to its own submittal procedure:
- Project, area and finish-schedule reference.
- Submission identifier, revision and date received.
- Supplier, stone name and available batch or slab identifiers.
- Sample type, finish, thickness and treatments disclosed.
- Photograph references and physical sample storage location.
- Accepted characteristics and specific exclusions.
- Linked drawing revision and outstanding technical reviews.
- Decision, reviewer, date and required resubmission items.
- Exact scope of any release for procurement or fabrication.
Instead of “stone approved,” a useful record could say: “Finish and visual range accepted for lobby wall review against sample set S-04, revision B. Panel layout and fixing details remain subject to separate review.” This is an illustrative coordination note, not a substitute for the project’s contractual approval wording.
8. Carry the approval through production
Agree who retains the benchmark, who compares production against it and how an exception is reported. If the finish, source, selected lot or approved geometry changes, identify which approvals need to be revisited. Keep superseded submissions clearly marked so the factory and site use the same current references.
For composed walls, connect the sample record to the approved bookmatched marble layout. For floors, connect it to the setting-out and tonal-distribution plan.
Questions to resolve before ordering
Does a sample reserve the material? Record reservation and availability separately with the supplier; a visual approval does not itself describe a reservation arrangement.
Can photographs replace physical samples? They are useful for sharing references and layouts, but screens and lighting can change apparent colour. Agree which physical and photographic records control each decision.
What should the first enquiry include? Send the application, drawings, quantities, programme, desired finish and visual references. Explore VeraMarbles project support or discuss your sample and production requirements with our team.