Allophane from Ohneaux, Ardennes, Belgium– micromount as unique piece
This micromount specimen contains several pale, yellowish-white aggregates of Allophane with its typical earthy texture. The porous areas appear matte and powdery, with an irregular surface. While visually modest, the material is characteristic for this amorphous clay mineral.
Allophane is a hydrous aluminum silicate typically formed through the weathering of volcanic ash or in aluminum-rich soils. Due to its amorphous nature, it does not form crystals but appears as fine-grained or gel-like masses. In collections, it is mainly valued for the systematic documentation of secondary silicate phases.
Geology & Origin:
Ohneaux in the Ardennes is part of a geologically complex region with metamorphic rocks and local clay mineral occurrences. Allophane forms secondarily in weathered zones and is only rarely found in collectible quality. The locality is therefore of special interest to systematically focused collectors.
This table is for general information and orientation, although the sizes of the stones may vary. In addition, this specification is handled differently from region to region.
Sizes
Description
approx. Sizes in mm/cm
approx. Sizes in INCH
Capsule
Capsule
0.1–0.5 mm in a transparent hard capsule (approx. 1 cm)
capsule contents 0.1–0.5 mm
capsule contents 0.004–0.02 in
TN/mm
Micromount (TN = Thumbnail)
everything fitting in a TN Perky box or a MM box of approx. 1 in
approx. 0.5–2.5 cm
max. 1 in
Min
Miniature specimen
will not fit a TN or MM box anymore
approx. 2.5–5 cm
approx. 0.2–1.0 in
Scab
small cabinet specimen
approx. one-third to half a hand size
approx. 5–9 cm
approx. 1.0–2.0 in
Cab
cabinet specimen
full hand size
approx. 9–15 cm
approx. 2.0–3.5 in
large Cab
large cabinet specimen
approx. two hand sizes
approx. 15–30 cm
approx. 3.5–6.0 in
very large Cab
very large cabinet specimen
everything larger, no upper limit
Abbreviations commonly used in mineralogy.
Abbreviation
Meaning
xl
single crystal, possible with matrix
xls
noticeable crystals
(xl)
embedded or damaged
(xls)
embedded or damaged
MASS
massive and/or amorphous pieces
TYP
type locality of the original description
SWUV
shortwave-UV-reaction
UV
ultraviolet reaction
SC
self-collected
U
unique (single unique piece)
Usage Instructions
This product is ideal as a collector's item, decorative element, teaching material, or for scientific and exhibition purposes.
Legal Notices
Safety
We accept no liability for damages resulting from improper and/or non-recommended use. Please carefully assess the suitability of the product before any alternative use.
Responsible Provider
Mikon Mineralienkontor GmbH Steinslieth 11 D-37130 Gleichen OT Klein Lengden
