Liberty Cap vs Philosopher's Stone
Psilocybe semilanceata compared with Psilocybe tampanensis — how to tell them apart in the field.
This is a dangerous confusion.
At least one of these species is toxic. Never eat a wild mushroom based on a photo comparison alone — verify with local experts.
Liberty Cap
Psilocybe semilanceata
ToxicPsychoactive
Philosopher's Stone / Magic Truffle
Psilocybe tampanensis
ToxicPsychoactive
How to Tell Them Apart
Similar size range but has a distinctly pointed, nipple-like cap with a gelatinous pellicle. Grows in temperate grasslands. Does not produce sclerotia.
Side-by-Side Identification
| Trait | Liberty Cap | Philosopher's Stone |
|---|---|---|
| Cap | 0.5–2.5 cm across. Distinctly conical to bell-shaped with a pointed nipple (umbo) at the top that persists even when the cap opens. Cream to light brown when dry, darker olive-brown when wet. The surface has a translucent, slightly sticky quality when moist — you can see the gills through the cap if you hold it up to light. Develops a wavy margin with age. | 1-2.4 cm across. Convex to plane, sometimes with a slight umbo. Ochraceous-brown to straw-colored, paler when dry. Smooth, slightly sticky when moist. Hygrophanous. |
| Gills | Narrowly attached to the stem (adnate). Start pale grey, mature to dark purple-brown as spores develop. Edges remain lighter — a white or pale fringe along the gill edge is a good diagnostic feature. | Adnate, medium-spaced. Brown to dark purple-brown with age. Edges lighter. |
| Stem | 4–10 cm tall but only 1–3 mm thick — extremely slender and wiry. Pale cream to yellowish, often with a slight blue-green tinge at the base when handled. Tough and flexible — you can bend it without it snapping. No ring. | 2-6 cm tall, 1-2 mm thick. Thin, equal. Yellowish-brown, slightly darker at the base. Bruises blue when handled. |
| Spore print | Dark purple-brown to blackish. Essential for confirming ID — many small brown mushrooms look similar but have different spore colors. | Purple-brown to dark purple-brown. |
| Bruising | — | Blue-green bruising on stem and cap, sometimes slow to develop. Sclerotia also bruise blue when cut. |
| Odor | Slightly musty, like damp hay. Nothing distinctive. | — |
| Habitat | Unimproved grasslands — sheep and cattle pastures that haven't been treated with artificial fertilizers. Grows in the grass, not on dung. Loves acidic, boggy soil. Often found on hillsides, moorlands, and old meadows. Doesn't grow in gardens, forests, or plowed fields. | The single wild collection was from a sandy meadow in a deciduous area. In cultivation, sclerotia form readily in grain or grass seed substrates. The natural habitat preferences remain poorly understood due to the extreme rarity of wild collections. |
| Season | September through November in the Northern Hemisphere. Triggered by the first cold rains after summer — usually when night temperatures drop below 10°C. Peak season is mid-September to mid-October in the UK and Northern Europe. | The only wild collection was made in September. In cultivation, sclerotia form year-round under controlled conditions. |
Found one of these in the wild? Don't rely on memory — identify it from a photo with Orangutany and check it against both species before you touch it.