Welcome to FrOg On-Line #2001-04, Monday, May 14, 2001
Contents
========
1. Introduction
2. Follow-Up to The Home Lab
3. "Subscriber" List
1. Introduction
===============
Greetings. Hopefully, y'all are recovered from the NJESA Show.
Sunday, April 29, in the saddle area between the Passiac and Noble Pits, one
of the collectors digging there asked to subscribe to FrOg On-Line, and gave me
a piece of paper with his e-mail address. Unfortunately, I lost it, and I've
completely forgotten both his name and his e-mail address. The only things I
do recall is that he is a Caucasian male, and he works for SAIC (Science
Applications International Corp.). If anyone knows his name or a-mail address,
please let me know, or have him e-mail me.
The FrOg On-Line Archive has a new web address:
"http://www.njminerals.org/FOINDEX.HTM"
Chris Thorsten continues to host the archive. His home page is now at
"http://www.njminerals.org"
I have tried it; it works great.
This issue consists mainly of a discussion of Chris Thorsten's home lab work on
Monazite, first reported in FrOg On-Line #2001-03.
The next issue, already in preparation, will be dedicated to a discussion of
Charlesite and two of the FrOg mineral lists.
As far as I know, there are no new activities or events to be added to what was
in FrOg On-Line #2001-03, so see that issue for the schedule of events.
Enjoy.
2. Follow-Up to The Home Lab
============================
From: "earl verbeek" <earlverbeek@hotmail.com>
To: chris@atomic-pc.com
Cc: mattison@thunder.nws.noaa.gov
Subject: monazite
Date: Mon, 09 Apr 2001 10:43:51 -0400
Good morning Chris,
Just read the latest FrOg issue and mention of monazite fluorescing under
unfiltered UV. Minor correction there, as what you see is not fluorescence but
simple reflection, in this case of the very strong Hg emission line at . . .
what? . . . 536 nm or so? I can't remember the exact wavelength, but it's
in the green portion of the spectrum and is a whopper of a peak. It's filtered
out by the SW filter, so monazite generally will not fluoresce green with a
filtered SW lamp (unless it's uranyl-activated, like the Madagascan material
seems to be), but the reflection of the Hg emission line under unfiltered SW is
a good test.
By the way, a number of other rare-earth minerals do this too, and it's
fortunate they do, because some of them can be quite inconspicuous in their
host rock. The Mountain Pass, CA ores are a case in point, as some of them are
just loaded with rare-earth minerals but look like ordinary rocks until you
hold them under that unfiltered lamp.
---------------
From: "earl verbeek" <earlverbeek@hotmail.com>
To: mattison@thunder.nws.noaa.gov, everbeek@nac.net, chris@atomic-pc.com
Subject: Re: monazite
Date: Mon, 09 Apr 2001 14:34:48 -0400
Hi Bill and Chris,
I have no objection to using my little note in a FrOg newsletter, IF it's OK
with Chris. I know some people are sensitive about corrections appearing in
print, and I am one of them unless the correction is done tactfully and with an
intent to help. I am not the one to judge whether that impression comes
through in my note, so it's Chris' call.
Most monazite is tan to brown in daylight, and quite a few other rare-earth
minerals are various pale colors, so they tend not to stand out very well in
the rocks that contain them. As far as I know the rare earths are not
chromophores, thus explaining the general lack of vivid coloration. And Bill,
you guessed just right, these minerals do selectively reflect light with a
wavelength near that of the mercury resonance line. It's almost like holding
up a mirror. When looking at unfiltered SW light we're not particularly aware
of how much green light is in it, but the selective reflection from the rare
earth minerals shows it quite nicely.
If I remember I'll try to look up an absorption spectrum for monazite and send
it to you. I don't know if I have one on file, but I know where to look on the
Internet. Bless you, CalTech.
Cheers- Earl
---------------
Date: Tue, 10 Apr 2001 00:55:57 -0400
From: Chris <chris@atomic-pc.com>
To: everbeek@nac.net, Bill Mattison <mattison@thunder.nws.noaa.gov>
Subject: Re: monazite
Earl and Bill,
it's cool w/ me... I think it may be helpful to others to print it also. I
don't think mercury-line reflection is a well-known or obvious enough fact that
someone's going to pounce on me and say "duh", so I'm okay with that... but I
appreciate Earl's consideration nonetheless.
By the way, the Buckwheat monazites and synchysites that I've seen in the
collections of the FMM, Steve Kuitems, and Joe Klitsch are typically pale
yellow, honey-lemon yellow (like a Luden's cough drop) or even pinkish-yellow -
and usually transparent. Steve and Joe both have found quite a few of these
tiny crystals on the dump. John C. has a couple of exceptional ones he's shown
me, too. Unfortunately, there are none that would qualify as "cabinet
specimens"... sorry, Bill, no macro monazites yet : )
-Chris Thorsten
---------------
Sender: mattison@thunder.nws.noaa.gov
Date: Tue, 10 Apr 2001 12:27:34 +0000
From: William Mattison <mattison@thunder.nws.noaa.gov>
To: Chris Thorsten <chris@atomic-pc.com>, Earl Verbeek <everbeek@nac.net>
Subject: Hg Emission spectra.
Interesting discussion so far. I'd like to see this phenomenon for myself one
of these days.
This past month, Rod Towers of the Gem, Lapidary, and Mineral Society of
Montgomery County, Maryland (the local club to which I belong) gave me a
holographic diffraction grating (6000 lines per inch), purchased from Edmund
Scientific. The accompanying pamphlet (by Stephen Jacobs of the Optical
Sciences Center at the University of Arizona) lists the following emission
peaks for mercury: 577 and 579nm (yellow, a doublet), 546nm (green), 436nm
(blue), 365nm (lw uv), 313nm (mw uv), and 254nm (sw uv).
Bill.
---------------
Date: Wed, 18 Apr 2001 22:16:59 -0700
From: Richard Bostwick <rbostwick@worldnet.att.net>
To: William Mattison <mattison@thunder.nws.noaa.gov>
Subject: Re: FrOg On-Line #2001-03.
Regarding Chris's observation about the "fluorescence" of Franklin monazite:
1) According to Sterling Gleason, who gives Murata and Bastron of the USGS
credit for the information, monazite does not fluoresce under shortwave UV but
is selectively reflecting the green light emitted by the unfiltered Hg arc.
(Gleason p. 196) This is confirmed in the "Henkel Glossary" in the monazite
entry on p. 57 in the brackets which indicate placement of the information by
the editors, Pete Modreski and Earl Verbeek. I have seen the phenomenon (though
I have not had a chance to confirm it in Franklin monazite) and it certainly
looks like fluorescence. However, the fact that one doesn't see green under
filtered SW is a clue.
2) Chris deserves a lot of credit for this observation, which confirms an
important diagnostic use of shortwave UV. In other words, this is probably the
easiest way by far to identify monazite-(Ce) from Franklin - a very rare and
desirable mineral from that locality. Thank you, Chris, for passing along that
information.
Dick Bostwick
---------------
Date: Sun, 13 May 2001 16:53:06 -0400
From: Doug Mitchell <DMitchell@compuserve.com>
Subject: Monazite "fluorescence"
To: William Mattison <mattison@thunder.nws.noaa.gov>
Hi, Bill--
Chris Thorsten's report in FrOg On-Line #2001-03 used the unfiltered shortwave
UV test for monazite on a micro crystal in a Buckwheat Dump dolomite. He
referred to the green "fluorescence" of the crystal under the unfiltered light
of a shortwave UV lamp. According to "Ultraviolet Guide to Minerals", by
Sterling Gleason, this green appearance is not fluorescence, but rather a
colored reflection of visible light from the shortwave UV lamp. The UV lamp's
visible light has unusual spectral features that emphasize a green reflection
caused by neodymium, thus establishing the substantial presence of rare earth
elements. Bastnaesite, and probably some other rare earth minerals, will react
similarly to this test.
Given this explanation, the test should work equally well if you put a piece of
glass or any UV absorbing material over the shortwave UV lamp. This should
make the matter of UV protection simpler.
--Doug
P.S. Please feel free to include this in a FrOg online.
3. "Subscriber" List
====================
NJ Larry Berger lberger1@mindspring.com
NC Alan Borg aborg@brinet.com
NY Dick Bostwick rbostwick@worldnet.att.net
NJ Mark Boyer mboyer@pace2001.com
CA Kevin Brady ktbrady@temvalley.com
PA Bob Carnein ccarnein@eagle.lhup.edu
VA Peter Chin Peter.Chin@USPTO.GOV
NJ John Cianciulli rockman@warwick.net
NJ John Corsello corsello@bellatlantic.net
CT Denis De Angelis rockden@mindspring.com
CA Fred Devito devito@sierratel.com
FL Sandra Downs SdownsFLA@aol.com
NY Howie Green Royal53@worldnet.att.net
MD Gary Grenier william.grenier@mercantile.net
MN Tim Hanson tim@ens.net
NY Tema Hecht thecht@worldnet.att.net
CA Andy Honig andym@lightspeed.net
CA Mark Isaacs isaacsmark@hotmail.com
MI John Jaszczak jaszczak@mtu.edu
NY Carl Kanoff MCDKan@clarityconnect.com
NJ Steve Kuitems skuitems@eclipse.net
FL Roy Lambert rlambert@ufl.edu
NY Donald Lapham donald_lapham@fmc.com
NY Greg Lesinski Gslrocks@aol.com
PA Jay Lininger matrix@redrose.net
PA Mike Logan mikelogan@sprintmail.com
CO Peter Marikle peter.a.marikle@lmco.com
MD Bill Mattison mattison@thunder.nws.noaa.gov
CA Dan McHugh dmchugh@eee.org
NJ Dan McHugh Sr. dansart1@aol.com
VA Curt Michanczyk CurtMich@aol.com
CA Doug Mitchell DMitchell@compuserve.com
CO Pete Modreski pmodresk@usgs.gov
WA Don Newsome uvsystems@aol.com
NJ Jeff Osowski jvotmo@blast.net
AZ George Polman polmans@compuserve.com
NJ Nathan Schachtman nschacht@voicenet.com
NY Paul Shizume s1153fam@aol.com
MD Steve Shramko steven@cyberocks.com
NJ Dave Slaymaker dh10000@yahoo.com
CT Charles Sloan csloan@snet.net
CA Jane Grover-Smith ANGLESEA@webtv.net
CA Kent Smith kentnorwood@email.msn.com
NJ Chris Thorsten chris@atomic-pc.com
NJ Jim Tozour jtozour@home.com
NJ Earl Verbeek everbeek@nac.net
PA John Vidumsky john.e.vidumsky@usa.dupont.com
PA Eric Weis weis@pnpa.net
NM Dru Wilbur dwilbur@nmt.edu
VA David Woolley DAVEWOOL@webtv.net
FL Herb Yeates herb@simplethinking.com
CA Wayne Young Wayney@us.ibm.com