Willemite


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willemite

[′wil·ə‚mīt]
(mineralogy)
Zn2SiO4 A white, greenish-yellow, green, reddish, or brown mineral that forms rhombohedral crystals and exhibits intense bright-yellow fluorescence in ultraviolet light; a minor ore of zinc.

Willemite

 

(after King Willem I of the Netherlands), a mineral, Zn2SiO4 (73.0 percent ZnO, 27.0 percent SiO2). Admixtures of Mn2+ are common. Crystallizes in a trigonal system. The structure is complex, composed of tetrahedrons of SiO4 and ZnO4 linked by common oxygens. Prismatic or acicular crystals are rare; they are usually granular or radial-fibrous aggregates, incrustations, and so on.

Willemite is colorless, greenish, or yellowish brown, and it phosphoresces brightly in ultraviolet light or cathode rays. Hardness on the mineralogical scale, 5-6; density, 3,890-4,180 kg/m3. It formed both in oxidation zones of lead-zinc deposits and in certain contact-metasomatic deposits (at Franklin in the USA). It is used as a zinc ore. It is also used to make fluorescent screens in cathode-ray tubes and other instruments.

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Penarth switched off soon after, allowing Bath to gain in confidence and hit back to 3-2 before Willemite made it 4-2 at the break.
Linear combination fitting of the XANES and XAFS region of the absorption spectra showed that the speciation of Zn for the hotspot at the edge of the pore and further into the soil matrix chosen in the intact samples was very similar and in forms resembling hydrozincite, Zn-sulfate, and willemite (Table 3, Fig.
Standards included jadeite (Na, Al), diopside (Si, Ca, Mg), rutile (Ti), hematite (Fe), spinel (Mn), crockoite (Cr), willemite (Zn) and apatite (F).
Some of the "Calendar Girls" packing bags at Sainsbury's (from left), Kim Wood, Mandy Barwick, Kate Willemite and Sarah-Jane Longbottom COLLECTING CASH "Calendar Girls" and helpers (from left), Victoria and Hamish Malcolm, Sarah Whitelaw, Paula Farmer, Rosalyn Raine and Scarlett Whittell
Finally, David Sliwinski (Brock) described work on the [Si.sup.29] NMR of synthetic forsterite [Mg.sub.2][SiO.sub.4], and willemite [Zn.sub.2][SiO.sub.2] doped with paramagnetic transition metal ions.
To their credit, Exeter started the second period full of intensity and purpose, but Andrew Willemite quickly dampened their enthusiasm by adding a fourth goal with a fine finish from a well-worked penalty corner.
Franklin and Sterling Hill have also produced some of the finest crystal specimens known of several mineral species, notably franklinite, zincite, willemite, and rhodonite.
The Vale side now enjoyed the majority of possession and, aided by some ill-discipline from Cardiff & Met - who were on the receiving end of four yellow cards and, at one point, were reduced to nine men - finally got on the scoresheet when a wellworked penalty corner was deflected in at the right post by Andrew Willemite.
Penarth's senior side drew 2-2 with Whitchurch, thanks to goals from David Joyce and Andrew Willemite, while the 3rd XI began their pre-season preparations with a fixture against a Cardiff Medics team set to compete two divisions higher, going down 4-3 with goals from James Kidby (2) and Dave Watkins.
849 Franklinite in Willemite, Franklin New Jersey, no.
Willemite is rarely found in well-formed, translucent to transparent crystals.
Finally, there was the "Fluorescent Tent": a 15 X 25 foot-long tent which contained hundreds of Franklin-Ogdensburg ore specimens of willemite, calcite, esperite and many other rarities carefully selected for their unique combination of patterns and associations.