MetaDi monocrystalline suspension
Buehler's monocrystalline diamond suspensions for specimen polishing, with carrier variants, nominal sizes, package codes, and limits of formulation and safety evidence.
Tags: abrasives, polishing, metallography
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Product identity and morphology
Buehler lists two 6 µm monocrystalline MetaDi suspensions in 16 oz [0.47 L] spray packages. Order 40-6542 for the oil-based variant intended for water-sensitive specimens and 40-6532 for the solvent-free water-based variant. Check carrier compatibility for the specimen and method. Buehler, Diamond suspensions and paste.
Buehler describes the single-crystal MetaDi diamonds as sharp and blocky. Its 6 µm comparison with multifaceted MetaDi Supreme is specific to the material, cloth and preparation parameters in the guide. Buehler, Polishing Application Guide, pp. 6 and 7.
Nominal sizes and package variants
The following codes and color designations are listed in Buehler's ordering table. Volumes retain the manufacturer's rounded metric equivalents. The 16 oz packages have spray nozzles. Buehler ordering information.
| Diamond size | Color | Water-based, 16 oz [0.47 L] | Water-based, 32 oz [0.95 L] | Water-based, 1 gal [3.8 L] | Oil-based, 16 oz [0.47 L] |
|---|---|---|---|---|---|
| 1 µm | Blue | 40-6530 | 40-6530-032 | 40-6530-128 | 40-6540 |
| 3 µm | Green | 40-6531 | 40-6531-032 | 40-6531-128 | 40-6541 |
| 6 µm | Yellow | 40-6532 | 40-6532-032 | 40-6532-128 | 40-6542 |
| 9 µm | Deep red | 40-6533 | 40-6533-032 | 40-6533-128 | 40-6543 |
| 15 µm | Brown | 40-6534 | 40-6534-032 | 40-6534-128 | 40-6544 |
The ordering table labels sizes in micrometers and gives no grading standard, percentile definition, maximum grain size, or lot distribution. Buehler ordering information.
Synthesis. These are nominal product designations rather than measured size distributions. The 1 µm label does not promise a 1 µm scratch depth or surface roughness.
Related formulations
MetaDi Supreme is polycrystalline. MetaDi Combo combines monocrystalline suspension with extender for automated dosing. MetaDi monocrystalline paste and MetaDi II paste are separate paste products. None is another package size of the standard suspension. Buehler product descriptions.
Buehler's guide distinguishes natural monocrystalline paste from synthetic MetaDi II paste. That distinction does not establish the origin of diamond in the suspension. The guide also identifies diamond embedding as a concern in soft materials and describes paste as a possible alternative. Its claims about MetaDi Supreme safety and performance do not transfer to monocrystalline suspension. Polishing Application Guide, pp. 6, 7, and 14.
Carrier and property evidence
The US water-based SDS groups Supreme, monocrystalline, and Combo products under ID 1352983. Section 1 explicitly includes the water-based codes in the table above. Section 9 gives pH 6.5 to 8.5 for that grouped product and supplies no viscosity or solubility data. Section 3 does not disclose a complete formulation. Section 8 names 1,2-propanediol and diamond without concentrations. The product-page term solvent-free therefore does not establish a carrier of pure water or the absence of every organic ingredient. Water-based US SDS, sections 1, 3, 8, and 9.
The oil-based US SDS, ID 1353241, explicitly includes codes 40-6540 through 40-6544. Section 3 lists hydrotreated light petroleum distillates at 65 to 95 percent. Section 9 reports a dynamic viscosity of 85 to 100 cP without a measurement temperature, lists solubility as insoluble without naming the test medium, and provides no pH data. These disclosures do not establish diamond concentration or a dosing specification. Oil-based US SDS, sections 1, 3, and 9.
Safety discrepancy and cleaning limits
The oil-based US SDS labels the mixture unclassified in section 2, while section 3 classifies the disclosed petroleum ingredient for aspiration hazard. Ingredient classification is distinct from mixture classification. The UK oil-based SDS lists the same product codes but classifies the mixture as hazardous to the aquatic environment, chronic category 2, H411. These jurisdiction-specific documents disagree on environmental classification. They do not establish whether the difference reflects formulation, regulatory criteria, or document maintenance. US SDS, sections 2, 3, and 12, UK SDS, sections 1, 2, 3, and 12.
The water-based SDS lists strong acids, strong bases, and strong oxidizers as incompatible. The oil-based SDS lists strong oxidizers. These chemical-storage statements do not qualify specimen or mounting-resin compatibility. Water-based SDS, section 10, oil-based SDS, section 10.
Synthesis. Oil-based selection for a water-sensitive specimen does not establish a compatible cleaning solvent. The reviewed sources provide no universal cleaning process for every specimen, mount, cloth, and carrier combination. Nominal grain size alone cannot determine polishing force, speed, time, finish, or removal rate. Specimen-preparation evidence also does not establish production deburring or dimensional-finishing capability.
Source provenance and coverage
Reviewed October 29, 2026, PDT. The product page has no displayed technical revision date. The 16-page Polishing Application Guide is marked copyright 2018 and document FN01465. The seven-page water-based US SDS is version 1.0, revised July 19, 2022. The seven-page oil-based US SDS is version 2.0, revised October 17, 2023. The nine-page oil-based UK SDS is version 4.0, revised October 18, 2023. Each SDS covers more codes than the current product ordering table, so its scope does not prove current availability of additional grades.
The cited documents were publicly accessible without login. The linked shop page for 40-6530 redirected to login and was not used as product evidence. Full additive composition, lot-specific grain distribution, diamond concentration, shelf life, and specimen-specific process qualification remain outside verified coverage. No independent performance study was used.
Related reference
Monocrystalline diamond abrasive covers the broader abrasive class.