Why must the percentages add up to 100%?

The entire sample passes through the sieve series; every grain is either retained on a sieve or falls into the pan at the bottom. The retained percentages must therefore total 100%. If the total deviates noticeably, there has been sample loss or a measurement error and the report is not reliable.

What is the multiplier column for?

It is used in the AFS/GFN calculation. Each sieve size has a multiplier defined in the standard, and the percentage retained on that sieve is weighted with it, so finer grains influence the result more. Millimetre-based fractions have no multiplier column because no GFN is calculated.

If two sands have the same AFS, are they the same sand?

No. AFS is an average fineness value and the same average can be reached with different distributions. One sand may be concentrated in a narrow band while another is spread widely. A narrow distribution usually behaves more predictably. This is why you should look at the distribution across the sieves, not only at the AFS number.

Is moisture measurement part of the sieve analysis?

It is a separate measurement but they are evaluated together. Damp sand does not pass through the sieves correctly and clumping distorts the analysis, so the sample is dried beforehand. Moisture is then measured separately before shipment — it is a critical value for applications that require dry sand, such as construction chemicals and precast.

How to Read a Sieve Analysis | Sand Test Report Guide

Q: Can I see the analysis report before ordering?

Yes. Click the fraction cards on the product pages to see that fraction's sieve analysis on screen and download the technical data sheet (TDS). When you place an order we also share the analysis of the batch actually shipped.

What Does a Sieve Analysis Tell You?

A sieve analysis sets out the grain size distribution of a sand sample numerically. The sample is passed through a series of sieves ordered from the largest to the smallest aperture, and the amount retained on each sieve is weighed. The result is the identity card of that sand: two sands sold under the same product name will perform differently if their distributions differ.

The Columns in the Report

Sieve: the standard designation or number of the sieve.
Sieve (mm): its aperture. Grains larger than this aperture stay on the sieve.
Retained %: what percentage of the sample was held on that sieve. This column is the core of the analysis.
Multiplier: present only in analyses where AFS is calculated; the weighting coefficient of each sieve size.
Total: the sum of all retained percentages — it must be 100%.

How to Read It: Three Practical Checks

1. Does the total come to 100%? This is the first place to look. If the total deviates there has been sample loss, and the rest of the report cannot be trusted.

2. Where is the distribution concentrated? If most of the percentage sits on two or three neighbouring sieves the sand has a narrow distribution; if it is spread over a wide band the distribution is broad. A narrow distribution gives more predictable results in filtration and in casting surfaces.

3. How much sits at the extremes? Are the coarse grains retained on the top sieve and the fine dust falling to the bottom within acceptable limits for your application? In filter sand, fine dust causes pressure loss; in construction chemicals, coarse grain spoils the surface texture.

How Does the AFS/GFN Come Out?

The percentage retained on each sieve is multiplied by that sieve's factor, and the sum of these values is divided by the total percentage. The resulting number is the GFN. AFS therefore derives from the whole distribution, not from a single sieve — which explains why two sands with the same AFS can behave differently.

We collected the measured GFN values and micron equivalents of the ten AFS grades we produce in a separate chart: Silica Sand AFS Chart

What to Check When Comparing Suppliers

From which date and which batch was the analysis taken? An old sample report does not represent the sand that will be shipped today.
Is the report issued per batch, or is it a single promotional example?
Are moisture and chemical analysis provided alongside the sieve analysis?
Does the same fraction give comparable results across different shipments? In serial production this is what really matters.

Review Our Analyses

Click the fraction cards on the product pages to see each fraction's sieve analysis on screen and download the technical data sheet. For a specific fraction or batch analysis, write to us.

Related pages:

How to Read a Sieve Analysis: A Line-by-Line Guide