Sample Preparation and Examination for Petrography

In 1849 when Henry Sorby, the father of petrography, prepared a thin section, he may not have envisioned that one day his technique would be used to analyze many diverse materials such as ceramics, glass, concrete, cement, soils, biomaterials, and polymers, to name a few. Sorby demonstrated to the scientific community that by using simple techniques, one could reveal the microstructure of materials observed with a microscope. Although Sorby’s method of preparation was crude compared to the methods used today, his basic technique for preparing and examining a specimen has remained fairly similar.

There are two types of specimens routinely prepared for analysis, thin sections and polished bulk specimens. For polished bulk specimens, the surface is prepared for examination with a reflected light microscope.Thin sections, on the other hand, are extremely thin, generally 30µm or thinner, and are typically observed with a transmitted polarized light microscope. The chart to the right describes a general procedure required to prepare both thin sections and polished bulk specimens.

Since 1936, Buehler has been the world leader in developing and supplying high quality laboratory specimen preparation equipment and consumable products. Buehler’s experience paired with today’s technologies help deliver the fullest product offering for all applications. Together with our technical expertise and lab equipment, Buehler is prepared to be your materials preparation partner.

Buehler® Guide to Petrography

The specimen preparation stages include:

• Sectioning Specimen
• Impregnation & Encapsulation
• Trimming
• Surface Preparation Prior to Bonding
• Bonding
• Resectioning
• Grinding
• Polishing
• Microscopic Examination
• Image Analysis & Capture

Image Credit: Buehler

Delta PetroCut® Geological Cutter

The Delta® PetroCut Geological Cutter is a manually operated bench-top cutter. The Delta® PetroCut Geological Cutter is used for manually sectioning slices from rock specimens.

Features include:

• 10" (254mm) diamond blade capacity
• 3.75" (95mm) diameter cutting capacity
• Recirculating coolant
• X-Y positioning table
• Powerfull 4 Hp motor
• Safety hood lock and mechanical motor brake
• Lighted cutting chamber

Image Credit: Buehler

Image Credit: Buehler

Lapro® Slab Saw 24"

Features of the Lapro® Slab Saw 24" include:

• Lapidary Slab Saw for Cutting Minerals, Rocks and Concrete
• 24" (610mm) Diamond Blade with 9" (229mm) Cutting Depth
• Convenient Sloped Bottom with Drain, for Easy Coolant Removal
• Screw Drive Feed
• Three Adjustable Feed Rates
• Bronze Clutch Cam Engage/Disengagement Lever Actuated System
• Vise Opens up to 17" (432mm)
• Clear Cover to View Sample During Cutting
• Cast Iron Vise with Hardwood Jaws

Image Credit: Buehler

Trim Saw

Trim Saws are used for Cutting Minerals, Rock and Concrete.

6" Buehler Trim Saw

Features of the 6" Buehler Trim Saw include:

• Manual Saw Feed
• Self-aligning Table-top for Easy Removal
• Adjustable Blade Guard
• Optional Rock Vise

10" BuehlerPower Feed Trim Saw

Features of the 10" Buehler Power Feed Trim Saw include:

• Automated, Clutch Activated Power Saw Feed and Shut-off
• Hand Feeding of Vice Option
• Toggle Switch for Independent Operation

Image Credit: Buehler

VibroMet® 2 Vibratory Polisher

Features of the VibroMet® 2 Vibratory Polisher include:

• Prepares geological, ultra-thin sections of 5 to 10 microns
• Utilizes hotizontal vibratory motion, 7200 cycles per second
• Produces superior quality and exceptional flatness
• Large, 12" (305mm) diameter bowl holds multiple samples
• MiniMet Thin Section Holder fits in standard VibroMet specimen holder

Image Credit: Buehler

PetroThin® Thin Sectioning System

This ultra-thin sectioning bench-top product will cut and grind down to 30um or less depending on the hardness of the material.

Features of the PetroThin® Thin Sectioning System include:

• Holds 5 different size glass slides
• Vacuum slide chuck
• Cooling system uses water or propylene glycol
• 8" (203mm) diamond blade capacity for cutting non-metallics
• 8" (203mm) cup wheel for grinding

Image Credit: Buehler

Isomet® Family

IsoMet® family consists of the following thin sectioning bench-top cutters.

IsoMet® Low Speed Saw

The features of the IsoMet® Low Speed Saw include:

• 5" (127mm) blade capacity
• micrometer
• 0-300 rpm

IsoMet® 1000 Precision Saw

The features of the IsoMet® 1000 Precision Saw include:

• 7" (178mm) blade capacity
• micrometer
• 0-950 rpm

The bench-top cutters can be upgraded with versatile accessories. They include:

• Rotating/Oscillating Vice for quicker cuts of large specimens
• Table saw for cutting out sections from PCB's and other specimens
• Goniometer for sectioning crystals along specific planes

IsoMet® 4000 Linear Precision Saw

The features of the IsoMet® 4000 Linear Precision Saw include:

• 8" (203mm) blade capacity
• micrometer
• 200-5,000 rpm

IsoMet® 5000 Linear Precision Saw

The features of the IsoMet® 5000 Linear Precision Saw is the same as that of IsoMet 4000, but include programmability and automatic serial cutting.

This information has been sourced, reviewed and adapted from materials provided by Buehler.

For more information on this source, please visit Buehler.