Aluminoceladonite Explained

Aluminoceladonite
Category:	Phyllosilicate
Formula:	K(Mg,Fe^2+)Al(Si4O10)(OH)2
Imasymbol:	Acel^[1]
Strunz:	9.EC.15
Dana:	71.02.02a.06d
System:	Monoclinic
Class:	2/m
Color:	Colorless when pure, green when ferrous iron-bearing
Fracture:	Micaceous
Opticalprop:	Biaxial (-)
Birefringence:	0.0190-0.0240
References:	^[2] ^[3]

Aluminoceladonite is a low-temperature potassium dioctahedral mica mineral which is an end-member in the illite-aluminoceladonite solid solution series. The chemical formula for aluminoceladonite is K(Mg,Fe²⁺)Al(Si₄O₁₀)(OH)₂.^[4]

Occurrence

Aluminoceladonite is often referred to as a rare mineral, though its actual abundance may be underestimated due to difficulty of identification. Aluminoceladonite, along with other phyllosilicate minerals in the illite-aluminoceladonite solid solution series, has been observed mainly among finely dispersed, mostly inter-layer-deficient, aluminium-rich potassium-dioctahedral mica varieties occurring in sedimentary rocks.^[5]

Notes and References

1. Warr. L.N.. 2021. IMA–CNMNC approved mineral symbols. Mineralogical Magazine. 85. 3. 291–320. 10.1180/mgm.2021.43. 2021MinM...85..291W. 235729616. free.
2. Web site: Aluminoceladonite: mineral information, data and localities. March 18, 2019.
3. Web site: Aluminoceladonite mineral data. March 18, 2019.
4. Drits. Victor A.. Zviagina. Bella. B. McCarty. Douglas K. Salyn. Alfred L.. 2010. Factors responsible for crystal-chemical variations in the solid solutions from illite to aluminoceladonite and from glauconite to celadonite. American Mineralogist. 95. 2–3. 348–361. 10.2138/am.2010.3300. 2010AmMin..95..348D. 62881038.
5. Zviagina. Bella B.. Drits. Victor A. Środoń. Jan. McCarty. Douglas K.. Dorzhieva. Olga V.. 2015. The illite–aluminoceladonite series: distinguishing features and identification criteria from x-ray diffraction and infrared spectroscopy data. Clays and Clay Minerals. 63. 5. 378–394. 10.1346/ccmn.2015.0630504. 2015CCM....63..378Z. 100485107.