Discussions

💬 Home 🔎 Search 📅 Latest

╳Discussions

💬 Home 🔎 Search 📅 Latest

Groups

Recent Images in Discussions

Messaggeria in lingua italianaAllanite-(Y), Seula.

6th Aug 2015 08:56 UTCOlav Revheim Manager

Does anyone have a reference for allanite-(Y) from here?

The reference listed on mindat: Pezzotta, F., Diella, V., Guastoni, A. (1999): Chemical and paragenetic data on gadolinite-group minerals from Baveno and Cuasso al Monte, southern Alps, Italy. American Mineralogist, Vol 84, pp 782–789: see http://www.mindat.org/locentry-78230.html does not mention allanite at all, and certainly not allanite-(Y).

Olav

6th Aug 2015 15:01 UTCReiner Mielke Expert

Like Olav says no mention of allanite See: http://www.minsocam.org/MSA/AmMin/TOC/Articles_Free/1999/Pezzotta_p782-789_99.pdf . The reference given http://www.mindat.org/locentry-78230.html should be removed.

6th Aug 2015 15:50 UTCDavid Von Bargen Manager

Actually allanite is mentioned in Figures 2 and 3. (may refer back to Grill 1937)

6th Aug 2015 16:47 UTCOlav Revheim Manager

Thank you David and Reiner.

The mention of allanite in the figures is stil not useful as a reference for allanite-(Y) as no suffix is mentioned. I was hoping for Grill aswell. I am not questioning the occurrence of allanite-(Y) as such, because allanite-(Y) is also listed in the amiminerals.forum, see http://forum.amiminerals.it/viewtopic.php?t=59 as one of the minerals occurring at Seula. I would like to learn how it was identified.

Olav

6th Aug 2015 16:55 UTCReiner Mielke Expert

Since then a lot of work has been done on allanite and the supposed allanite-Y may just be yttroepidote. There would have to be a modern analysis to be able to call it allanite-Y.

7th Aug 2015 12:40 UTCPaolo Bosio

The presence of Y-dominant allanites in the paragenetic association of gadolinite-group minerals at Baveno was reported at the end of the 1990s or at the beginning of the 2000s, but now I don’t remember in which publication. I have to check some possible works. Pezzotta et al. (1999), as already evidenced by David, mentioned in Figure 2 generic allanite and kainosite-(Y) as the REE-silicates in paragenetic association with gadolinite-group minerals.

In the less recent literature on Baveno the generic name allanite is always used. Grill (1937) described as allanite a black centimetre-sized prismatic crystal, showing a very fresh fracture surface [According to Gramaccioli (2003), crystals of such size have never been found later]. Grill & Scaini (1941) and Nova (1987) described as allanite dark brown to almost black elongated crystals, often grouped into fasciculated or fan-like aggregates, and millimetre-sized spherules. To allanite was also attributed, on the basis of optical properties, a black isotropic grain included in beryl (De Michele, 1968).

In the most recent literature some finds of allanite-(Ce) are reported from the quarries of Oltrefiume (Seula & Locatelli), Baveno: Ciriotti et al. (2006) described as Sc-bearing allanite-(Ce) [1.7-2% in Sc] grey-green to dark green millimetre-sized spheres, showing both smooth and bur-like surfaces; Piccoli et al. (2007) reported as allanite-(Ce) some tiny prismatic crystals analitically determined by Italo Campostrini. Allanite-(Ce) is also reported from cavities in the Mottarone-Baveno white granite facies at Rio Inferno, Omegna, in association with tourmaline, bertrandite, uranophane-beta, etc. (Albertini, 2000; Piccoli et al., 2007).

This is what I know about allanites from the Baveno granite.

Furthermore, in my opinion, in absence of analysis on the represented specimen, the photo minID: UHU-WEN should be indicated as generic ‘allanite’.

References:

Grill E. (1937): Titanite, allanite e gadolinite isotropa di Baveno. Atti Soc. Ital. Sci. Nat., 76, 384-388.

Grill E., Scaini G (1941): Itinerari mineralogici. Comune di Baveno: cave di granito del Monte Camoscio. Natura, 32, (2), 84-93.

De Michele V. (1968): Nuovo ritrovamento di berillo e presenza di allanite isotropa a Baveno. Natura, 59, (2), 129-131.

Nova G. (1987): Atlante dei minerali di Baveno. Ed. Gruppo Mineral. Lomb., Milano, 80 pp.

Pezzotta F., Diella V., Guastoni A. (1999): Chemical and paragenetic data on gadolinite group minerals from Baveno and Cuasso al Monte, southern Alps, Italy. Am. Miner., 84, (5-6), 782-789.

Albertini C. (2000): Ritrovamenti nel Rio Inferno, Brughiere di Omegna. Prima segnalazione nel granito di Baveno: uranofane-beta. Riv. Mineral. Ital., 24, (2), 88-92.

Gramaccioli C.M. (2003). Descrizione delle specie mineralogiche sinora osservate a Baveno. In: Buccellati G. (ed.), Granito di Baveno. Minerali, scultura, architettura. Università degli Studi di Milano, Arti Grafiche Amilcare Pizzi S.p.A., Milano, 180-194.

Ciriotti M.E., Kolitsch U., Blaß G., Vanini F., Varvello S., Stramba S., Bonacina E. (2006): “Insoliti” minerali di Baveno: “ordinarie” allanite-(Ce) e aeschynite-(Y). Micro (UK report), (1), 13-18.

Piccoli G.C., Maletto G., Bosio P., Lombardo B. (2007): Minerali del Piemonte e della Valle d'Aosta. Associazione Amici del Museo "F. Eusebio" di Alba, Ed., Alba, 607 pp.

7th Aug 2015 13:31 UTCOlav Revheim Manager

Thank you Paolo.

I really appreciate the thotoughness of your reply and the amount of work needed to refind/check the information and references!

best regards

Olav

Mindat.org is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2024, except where stated. Most political location boundaries are © OpenStreetMap contributors. Mindat.org relies on the contributions of thousands of members and supporters. Founded in 2000 by Jolyon Ralph.
Privacy Policy - Terms & Conditions - Contact Us / DMCA issues - Report a bug/vulnerability Current server date and time: April 25, 2024 09:43:57

Go to top of page