How to Make a Microscope Slide From a Spore Syringe

By The Spore Source · Updated September 26, 2026

Intended use. Our Psilocybe cubensis spore syringes are sold for microscopy, taxonomy and educational use only. Not for human consumption. This page covers preparing and viewing a slide, and nothing else.

In this guide

• What you need
• Set up a clean work surface
• How to make a microscope slide from a spore syringe, step by step
• Focusing from low power to high
• What cubensis spores look like on the slide
• Mounting fluids and optional stains
• Measuring spores
• Needle safety and disposal
• Cleaning up and storing the syringe
• Frequently asked questions
• Sources

What you need

You need very little to make a microscope slide from a spore syringe, and most of it is ordinary lab glass.

• A spore syringe with its sterile needle and alcohol pad. Every syringe we sell ships with both.
• Plain glass slides and cover slips. Cover slips are the thin squares of glass that go over the drop.
• A compound microscope with 4×, 10× and 40× objectives and a 10× eyepiece. A 100× oil immersion objective is useful but not required. Our guide to the best microscope for mushroom spores explains what to look for.
• Immersion oil and lens tissue, only if you will use a 100× oil objective.
• Nitrile gloves, if you want them. Our Sanitary Kit includes a pair of nitrile gloves, a face mask and three alcohol pads.
• A sharps container, or a heavy-duty plastic bottle with a tight screw lid, for the used needle.

Set up a clean work surface

Pick a table with good light, out of drafts, where the slide can sit flat. Wash your hands and wipe the surface down. A clean surface keeps dust and lint off the slide, and it keeps a syringe you plan to use again from picking up anything from the table.

Check that the slide and cover slip are clean and dry. Fingerprints on either one blur the image at high magnification, so hold slides by the edges.

How to make a microscope slide from a spore syringe, step by step

1. Shake the syringe for several seconds. Spores settle to the bottom and collect in clumps when the syringe stands still, and shaking spreads them back through the water.
2. Wipe the tip with an alcohol pad. The alcohol pads in our Sanitary Kit are 70% isopropyl alcohol.
3. Remove the cap and attach the sterile needle. Keep the needle’s own cap on until you are ready to dispense.
4. Put one small drop in the center of the slide. One drop is enough. Too much liquid lets the cover slip float and drift.
5. Lower the cover slip at an angle. Rest one edge of the cover slip on the slide beside the drop, then let it down slowly onto the liquid. Lowering it slowly this way keeps air bubbles to a minimum.
6. Deal with the needle and syringe right away. Put the used needle straight into your sharps container, then recap the syringe. The section on needle safety below has the details.

That is a wet mount, the standard way to look at spores in liquid. It is meant for looking at the same day, since the water under the cover slip slowly dries from the edges.

Focusing from low power to high

Total magnification is the objective’s number multiplied by the eyepiece’s. With a standard 10× eyepiece, the 4× objective gives 40×, the 10× gives 100×, the 40× gives 400× and the 100× gives 1000×. Always start with the lowest-power objective.

• 40×. Find the drop. Look for the edge of the cover slip or an air bubble to get the focus close.
• 100×. Spores and clumps appear as small dark specks. Move the slide until you find an area with scattered specks rather than big clumps.
• 400×. Individual spores are clearly visible. This is the working magnification for looking at shape and color. Use the fine focus knob to sharpen the image.
• 1000× with oil. Place a drop of immersion oil on the cover slip, then swing the 100× objective into the oil. Never swing the 40× objective back through the oil. It is not made for oil, and oil on it has to be cleaned off.

Our guide to what magnification you need to see mushroom spores explains what each step shows and why adding magnification beyond that does not show more detail.

What cubensis spores look like on the slide

At 400×, Psilocybe cubensis spores are smooth, thick-walled ovals, individually a translucent purple-brown and almost black where they pile up. Published measurements put them at roughly 11 to 17 micrometers long by 7 to 11 wide. Each has a germ pore, a small thin spot at one end.

Named cubensis strains all fall in this same range, so spores are not a reliable way to tell strains apart. The exception is pigment. Spores from albino strains carry little color and are harder to see, which makes an albino strain like Albino Penis Envy an interesting comparison next to a pigmented strain like Golden Teacher. Our guide to what mushroom spores are explains how spores form and why their color varies.

Mounting fluids and optional stains

Water is enough for cubensis. Brown and dark spores need no stain, and plain water does not distort their color or size, which is why mycological groups use it as a basic mounting fluid.

Stains are optional and mainly help with pale spores:

• Congo red stains cell walls and is the usual choice for colorless spores that are otherwise barely visible under a compound microscope.
• Melzer’s reagent is an iodine solution used as an identification test. Spores that turn blue to black in it are called amyloid, and spores that show no reaction are called inamyloid.

Treat any stain as a chemical. Read its label, use a small amount, and keep it off the microscope’s lenses.

Measuring spores

Measuring is what turns looking into taxonomy. You need an eyepiece graticule, a scale mounted inside the eyepiece, and a stage micrometer, a slide etched with a scale of known length. Line the two scales up to work out how many micrometers each graticule division equals, and repeat this for every objective, because objectives marked with the same number can differ slightly.

The Buckinghamshire Fungus Group in England and the Queensland Mycological Society in Australia both measure spores at 1000× with oil immersion, and the Buckinghamshire group notes that 400× gives only a rough idea of size. Measure at least 10 spores, including some larger and some smaller ones, and record the range and the average.

Needle safety and disposal

The needle is the part of this job most likely to hurt someone. Guidance on sharps from the FDA and the NIH comes down to a few rules:

• Put a used needle in a sharps disposal container immediately after use.
• If you do not have an FDA-cleared sharps container, a heavy-duty plastic household container can stand in. It should be leak-resistant, stay upright and have a tight, puncture-resistant lid; a plastic laundry detergent bottle is the FDA’s example.
• Do not throw loose needles in the trash and do not flush them.
• Do not try to bend or break a needle.
• Fill the container only to about three-quarters, then follow your community’s rules for disposing of it.

Keep syringes, needles and slides away from children and pets.

Cleaning up and storing the syringe

Cleaning up is the last part of learning how to make a microscope slide from a spore syringe, and it takes a minute. If you used oil, wipe it off the 100× objective with lens tissue as soon as you finish. Put used slides and cover slips in a container for broken glass rather than loose in a bag, since cover slips break easily. Wipe the work surface again and wash your hands.

Recap the syringe, wipe the outside, and put it back in the refrigerator, where it stays good for up to 90 days. Do not freeze it. Our guide to how long spore syringes last covers storage in detail, and our spore syringe vs spore print comparison explains how making a slide from a print differs.

Frequently asked questions

How many drops do I need for one slide?

One small drop is enough. More liquid makes the cover slip float and drift.

How do I avoid air bubbles under the cover slip?

Rest one edge of the cover slip on the slide beside the drop and lower it slowly at an angle. Lowering it slowly keeps air bubbles to a minimum.

What magnification do I need to see spores?

Individual spores are clearly visible at 400×. At 100× they appear as specks, and 1000× with oil immersion is used for measuring.

Do I need to stain cubensis spores?

No. Their dark pigment makes them visible in plain water. Stains such as Congo red help mainly with pale or colorless spores.

Why is my slide blurry at 400×?

Common causes are a floating cover slip from too much liquid, a dirty slide or cover slip, or immersion oil on the 40× objective. Sharpen the image with the fine focus knob.

How do I dispose of the needle?

Put it in a sharps container right after use, or in a heavy-duty plastic bottle with a tight lid. Never put a loose needle in the trash.

Can I use the same syringe again?

Yes. Recap it and keep it in the refrigerator, where it stays good for up to 90 days, and use a new sterile needle each session. Each syringe ships with one needle, and extra sterile needles come in packs of 5.

Sources

• Microbehunter, “Making a wet mount microscope slide”
• Queensborough Community College (CUNY), Laboratory Exercises in Microbiology (PDF)
• University of Wisconsin–Madison, Virtual Microbiology, “Microscopy and staining”
• Hartline, Microbiology Laboratory Manual, “Microscopy” (LibreTexts)
• Leica Microsystems, “What is Empty Magnification”
• Wikipedia, “Psilocybe cubensis” (spore measurements, citing Singer and Smith, 1958)
• Mycology Wiki, “Psilocybe cubensis”
• Wikipedia, “Psilocybe” (spore features)
• Buckinghamshire Fungus Group, “Mushroom Microscopy: Some General Information and Tips” (PDF, 2022)
• Queensland Mycological Society, “Procedures for Using Stains and Immersion Oil in Microscopy”
• Nikon MicroscopyU, “Linear Measurements (Micrometry)”
• U.S. FDA, “Sharps Disposal Containers”
• U.S. FDA, “Best Way to Get Rid of Used Needles and Other Sharps”
• NIH Office of Research Services, “Do’s and Don’ts: Safe Needle and Other Sharps Disposal”