Is variscite UV reactive?
Sometimes. The Handbook sheet for variscite, an aluminium phosphate, records no fluorescence; three lamp records give green under shortwave; longwave differs.
Sometimes, and mainly under shortwave. The Handbook variscite sheet prints no fluorescence, but three fetched records do: the International Gem Society gives dull green to green under shortwave from two Utah localities, a Fluorescent Mineral Society slab from Lucin, Utah, glows green at 255 nm, and Fluomin lists green, white and bluish white. Longwave reports disagree.
In short
- The sheet is silent. The Handbook of Mineralogy variscite sheet has no fluorescence, phosphorescence or UV wording. Method: a case-insensitive search for “uoresc”, “phosphoresc”, “luminesc” and “UV”, which catches the ligature pdftotext garbles; the same search finds the wording on the hemimorphite and willemite sheets, so the miss on variscite is real. Silence means nothing printed, not inert.
- Three records that do print a response. The International Gem Society variscite article gives dull green (Lewiston, Utah) or green (Fairfield, Utah) under shortwave, whitish green under longwave. The Fluorescent Mineral Society database, specimen 190 is a 9 × 12.5 cm slab from Lucin, Utah, with variscite green under a 255 nm LED, described as modest. The Fluomin variscite record lists green, white, bluish white and greenish white at 365, 320 and 254 nm.
- The shortwave-green rule. Set side by side, the one band-and-colour pair all three records credit to variscite is green under shortwave. A green nodule that glows green under a shortwave lamp is consistent with variscite on this evidence; one that shows nothing is not ruled out, because two of the sources describe the response as dull or modest and none gives a rate.
- Documented failure: longwave. IGS gives whitish green under longwave; Fluomin gives four colours; the FMS slab’s longwave response, blue, is credited to a white mineral whose identity the entry gives as unknown, not to the variscite. So a longwave glow on a variscite piece may come from something else in it, and a longwave-only lamp tests the band on which the records disagree.
- UV does not separate variscite from turquoise. The turquoise sheet is silent too; the Fluomin turquoise record lists bluish white under longwave, a colour also on Fluomin’s variscite list, and says stabilised turquoise is sometimes luminescent because of the stabilising product. The separating numbers are on variscite vs turquoise. UV exposure limits are in the ICNIRP 2004 guidelines on limits of exposure to ultraviolet radiation; this is not safety advice.
| Source | Material | Shortwave | Midwave | Longwave | Places named | On the variscite sheet? |
|---|---|---|---|---|---|---|
| Handbook variscite sheet | Variscite | Not printed | Not printed | Not printed | — | — |
| IGS variscite article | Variscite | Dull green (Lewiston); green (Fairfield) | Not stated | Whitish green | Lewiston and Fairfield, Utah | Fairfield yes (Clay Canyon, about nine km west of Fairfield); Lewiston no |
| FMDB 190 | Variscite slab with an unidentified white mineral | Variscite green (255 nm LED) | Not listed | Blue, credited to the unidentified white mineral | Lucin, Box Elder Co., Utah | Yes (Utahlite Hill, about eight km northwest of Lucin) |
| Fluomin 209 | Variscite | Green, white, bluish white, greenish white (254 nm) | Same four (320 nm) | Same four (365 nm) | Fairfield and Lewiston, Utah; Wisniowka Wielka Quarry, Poland | Fairfield yes; the other two no |
| Handbook turquoise sheet | Turquoise | Not printed | Not printed | Not printed | — | — |
| Fluomin 981 | Turquoise | Not listed | Not listed | Bluish white; stabilised turquoise sometimes luminescent from the product | — | — |
Does variscite glow under UV light? What the sheet says
Nothing. variscite is Al(PO4)(H2O)2 on the September 2026 IMA list: orthorhombic, usually fine-grained massive in nodules and crusts, hardness 4.5, density 2.57 to 2.61, pale green to emerald-green or bluish green. Its Handbook sheet prints optics, colours and localities but no luminescence. The search ran on the extracted text, case-insensitive, for “uoresc”, “phosphoresc”, “luminesc” and “UV”; the hemimorphite sheet (“may fluoresce bluish under SW UV”) and the willemite sheet both match. The same search finds nothing on the turquoise, wavellite, metavariscite or strengite sheets.
What silence means. A Handbook sheet that prints no luminescence has recorded none; it is not a statement that the mineral never glows. The variscite species page reports the same silence. For variscite the answer has to come from lamp records, and three were fetched for this page.
What the lamp records say
International Gem Society. Its variscite article, by Joel E. Arem, lists under Luminescence: dull green (Lewiston, Utah) or green (Fairfield, Utah) in SW; whitish green in LW from these localities, and under Luminescence Type, fluorescent, UV-long and UV-short.
Fluorescent Mineral Society. A search of its database for variscite returned one specimen, Fluorescent Mineral Society database, specimen 190, contributed by Michael Crawford on 16 July 2025: a 9 × 12.5 cm slab of green variscite from Lucin, Box Elder County, Utah. It says the variscite has modest green fluorescence under shortwave UV illumination, and its summary lists variscite green under a 255 nm LED. The contributor attributes the green to uranyl activation, read from a vibronic signature in a noisy emission spectrum; that is the contributor’s interpretation of one specimen, reported here as theirs. The entry also gives a radioactivity reading for the slab, which this page does not repeat; radioactivity questions go to is my mineral radioactive, and none of this is advice.
Fluomin. The Fluomin variscite record (© Gérard Barmarin) lists green, white, bluish white and greenish white under longwave (365 nm), midwave (320 nm) and shortwave (254 nm), names Fairfield and Lewiston, Utah, and the Wisniowka Wielka Quarry, Poland, as best localities, and gives no activator. It cites the Henkel Glossary and Robbins (1994).
The shortwave-green rule, and where it fails
The rule. Under shortwave all three records credit variscite with green: dull green or green (IGS), green (FMS), green among four colours (Fluomin). No other band and colour is common to all three. Each of the three names at least one Utah place that the variscite sheet also names: Fairfield (IGS, Fluomin) or Lucin (FMS). So the decision a collector can make is narrow: a green variscite nodule glowing green under a shortwave lamp behaves as the records describe.
Documented failures. Longwave: IGS whitish green, Fluomin four colours, and the FMS slab credits its longwave blue to an unidentified white mineral, not to variscite. Strength: IGS writes dull for one locality and FMS modest. Rate: none of the sources says what share of variscite glows, and the FMS database holds one variscite entry. The wavellite page is wavellite fluorescent found the same limits with five entries and its own ledger, not repeated here. Mechanism in general is on fluorescent minerals explained.
Will a UV lamp tell variscite from turquoise?
No. The turquoise sheet prints no luminescence. The Fluomin turquoise record lists bluish white under longwave, which is also one of Fluomin’s four variscite colours, and adds that stabilised turquoise is sometimes luminescent due to the product used during the stabilisation process. A glow can therefore come from variscite, from turquoise, from a stabiliser or from another mineral in the piece.
What does separate them. Numbers from the sheets: hardness 4.5 against 5 to 6, density 2.57 to 2.61 against 2.86, biaxial (−) against (+), and no copper against 7.81%, worked on variscite vs turquoise. The scratch-and-weigh tests for turquoise substitutes are on how to tell real turquoise from fake. Wavellite, a green phosphate that also glows on some records, is on wavellite.
Lamps, bands and safety
Use both bands and record both. The records above differ by band, so a shortwave result and a longwave result should be noted separately, with the locality; with a longwave lamp only, a blank under shortwave is not tested, not none. Lamp types are compared on the best UV lamp for mineral collecting. Variscite’s own numbers are on the variscite page and the comparison with turquoise on its own page.
Safety, in one line. Exposure limits for ultraviolet radiation between 180 and 400 nm are in the ICNIRP 2004 guidelines on limits of exposure to ultraviolet radiation; this page is not safety advice, and other hazards are routed to toxic minerals in a collection. More guides in the collecting guides. We hold no catalogue and nothing here is offered for sale; the wanted list is the only commercial route.