The center
Observe the inner cream-colored area and the way humus-associated forms move outward. Is the center integrated with the rest of the image, or sharply isolated?
Circular Chromatography: A Practical Journey Into Living Soil
A field-to-image learning journey
Let the soil
make a picture.
Circular chromatography turns a soil or compost extract into a pattern you can revisit, compare, and learn from—bringing careful process and direct observation into the same circle.
- 14:08step-by-step film
- 3–4replicas per sample
- 5 daystypical development
Circular chromatography is a qualitative method. It does not identify exact chemistry or replace a laboratory soil test. It offers a repeatable visual way to notice relationships, structure, vitality, and change.
01 · Watch
See the whole journey once.
The rhythm matters: prepare, move, pause, and observe. Watch JPI’s complete demonstration before beginning, then return to the chapters as you work.
02 · Make
From question to chromatogram.
Give every sample the same conditions. Consistency makes comparison possible—and the comparison is where learning begins.
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Ask & collect
Start with a real question.
What changed between two compost piles? How does one field compare with another? Collect at least 12 g from 12 representative points, combine the material, and write down the source, date, and question.
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Dry & prepare
Protect what you hope to see.
Air-dry the sample or keep heat below 120°F / 49°C to avoid damaging proteins and enzymes. Grind and sift it, then weigh 1.5 g for JPI’s filmed method.
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Extract & rest
Movement, pause, movement.
Add the 1.5 g sample to 50 mL of 1% sodium hydroxide. Swirl four seconds clockwise and four seconds in reverse, repeating for one minute. Rest 15 minutes; repeat for one minute. Rest 45 minutes; repeat once more. Then leave undisturbed for five hours.
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Prepare the paper
Make the circle measurable.
Use a 15 cm disc of Whatman No. 4 filter paper. Mark guide circles at 1½ inches and 2⅜ inches from the center. Cut a small central opening and roll two fresh ¾-inch paper wicks for each chromatogram.
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Let the picture rise
Sensitize, dry, then reveal.
In low, diffuse light, let 3–5 mL of 0.5% silver nitrate rise through the first wick to the inner mark. Remove the wick and dry the disc away from direct light. With a fresh wick, let 3–5 mL of the clear sample extract rise to the outer mark. Do not move the assembly.
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Develop & compare
Give the image time.
Hang the disc in shade or indirect daylight. It may change for hours or days and is usually complete by day five. Make three or four replicas for every sample; keep the consistent group and treat a lone outlier as a reason to review the process.
Before you begin
One method. Clearly recorded.
The film uses 1.5 g of soil or compost in 50 mL of 1% sodium hydroxide, a proportion JPI has found produces clear images. Pfeiffer’s published soil-and-compost standard uses 5 g in the same volume.
Do not mix protocols mid-series.
Either can be a documented method. For meaningful comparisons, choose one, repeat it exactly, and record the concentration with every image.
This is a chemical procedure.
Sodium hydroxide is caustic and can cause severe burns. Wear suitable eye and hand protection, prevent skin and eye contact, and follow the product’s safety data sheet. JPI recommends that beginners use a professionally diluted 1% solution. Silver nitrate stains and should also be handled with gloves and kept from direct light.
If contact occurs: rinse immediately with plenty of water and seek appropriate medical advice. Keep all chemicals labeled and away from children, food, and animals; follow local disposal guidance.
03 · Read
Look slowly.
Compare before concluding.
Learning to read chromatograms is closer to developing an ear for music or an eye for painting than reading a laboratory result. Start with replicas, recurring relationships, and the questions they raise.
Mineral zone
Notice the mineral field, its color, density, and structure. Pay special attention to how it meets the organic and biological region beyond it.
Living activity
This region is read in relation to organic matter, enzymes, and biological activity. Look for differentiation, radiating forms, and a gentle transition from the mineral zone.
The outer edge
The outer zone speaks to the quality of organic matter. Gold tones and coherent forms are traditionally valued; blotches and abrupt boundaries invite closer observation.
The chromatogram is not a verdict. It is an invitation to look again—at the sample, the process, and the life of the place.
When the image surprises you
Troubleshoot the process first.
The liquid stops moving
Humidity may be too low, the wick may be clogged, or contact may have been lost. Check the setup without shifting the paper. A moist atmosphere—often around 80% relative humidity—helps the liquid travel consistently.
There are rings or a “double exposure”
The wick likely lost contact and reconnected, or the assembly moved. Do not interpret the result; repeat it with a stable setup.
The image has spills or dark splotches
Fingerprints, splashes, or premature silver-nitrate discoloration can interfere. Handle only the edges and discard sensitized paper that has turned brown before use.
The whole image is evenly brown
The sample may be too concentrated or rich in colloids. Repeat with a lower sample concentration and note the change rather than forcing an interpretation.
The replicas do not agree
If one disc differs, set it aside and review the mechanics. If all differ substantially, restart the sampling and preparation process. Repeatability is part of the method.
04 · Record
Build a memory for the land.
A chromatogram becomes more useful when it stays connected to its place, conditions, and question. Use this field-note check before you finish.
Continue the journey
Practice grows the eye.
Observation is a practice
The picture is the
beginning of attention.
Make a series. Keep good notes. Return to the same places. Let pattern, change, and careful questions deepen your relationship with the living soil.
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