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Key Features

Physical Properties

Chemical Analysis

Quality Assurance Testing

Downloads

Downloads

—Chemical Analysis Test Data (PDF)

Material Safety Data Sheets:

  —English

  —Euro English

  —Euro Standard

  —Chinese

  —French

  —German

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  —Spanish

Key Features of Hess Pumice

• Specialized impurity extraction technologies allow for extremely high purity content (98% - 99.8%, depending on grade)

• Low unit weight (40 - 45 lbs per cubic foot, depending on grade)

• Consistent MOHS of between 5.5 and 6.1

• Superior friability characteristics

• Reported performance benefits of 25% - 50% over all other available pumice worldwide

• Near white color useful in many filler applications

• FOB pricing consistently the lowest in industry (depends on grade) due to advantageous economies of scale

• Large warehouse and unsurpassed processing capability allow for rapid response to customers' needs

• Custom blending available to meet the most exacting customer specifications

• Pumice, due to its amorphous characteristics, is not considered a health risk to the workers who handle it (See downloable Material Safety Data Sheets, below left)

• We can help customers secure economic freight rates from our location (Freight Collect)

• Confirmed 200+ year source of pumice reserves

Physical Properties

• Chemical Name: Amorphous Aluminum Silicate

• Hardness (MOHS): 6.1

• pH: 7.2

• Radioactivity: None

• Loss on Ignition (LOI): 5%

• Softening Point: 900 degrees C

• Water Soluble Substances: 0.15%

• Acid Soluble Substances: 2.9%

• Reactivity: Inert

• Appearance: Off-white powder

Chemical Analysis

• Silicon Dioxide - 87.4%

• Aluminum Oxide - 10.52%

• Ferric Oxide - 0.194%

• Ferrous Oxide - 0.174%

• Sodium - 0.128%

• Potassium - 0.099%

• Calcium - 0.090%

• Titanium Dioxide - 0.0074%

• Sulfate - 0.0043%

• Magnesium Oxide - 0.126%

• Water - 1.11 %

Ongoing Testing for Quality Assurance

Hess Pumice is continuously testing our product to ensure superior quality. Among the most common tests that we perform in-house are:

• Sieve Size Analysis (ASTM C-136)

• Particle Size Analysis by Laser Diffraction (ASTM B822-10)

• Whiteness (Datacolor “Check” method)

Typical Screen Analysis of Standard Grades Average Percent Passing Sieves

The above graduations are only typical. Normal production tolerances from the typical will be permitted. A trace is allowable on the next coarser sieve. (Click chart image above to enlarge; or download printable version)

Test Method: Split sample to 50 grams and shake for 10-20 minutes on Ro-Tap type sieve shaker. Use standard 8-inch U.S. Mesh testing sieves.

We have over 300 pumice grades available. For information on custom grades please call us at (800)767-4701.

We also submit product samples to outside laboratories for third-party verification in the following areas:

• Bacteria plate count

• Chemical analysis

• Bulk Density

We adhere to a strict inspection policy and are compliant with all ISO 9000/2008 standards.

Every lot of product (maximum of five pallets) is tested a minimum of two times during the production process with samples being retained for at least two years. All quality and sales records are retained electronically as well as in hard-copy form.

We go to great lengths to ensure customer satisfaction in both our product and the entire purchasing experience.