Dave-
Photomicrographs would be awesome. I appreciate that they will require a bit
more work to link them in to your database, and you would need a facility
for multiple images of the same mineral. I think their inclusion would be
worth the effort.
Cheers,
Cameron
On Tue, 5 Aug 2008 14:47:51 -0400, Eric Essene <[log in to unmask]> wrote:
>Dave and all,
> I am responding indirectly to Sengupta's comments. I'm not
>convinced that most of his categories are appropriate for this data
>base. Raman spectra have orientation effects that can be strong, such
>that a peak may disappear or reappear in different orientations,
>requiring that to be fixed in lower symmetry minerals. I think that
>compilations of such data are sufficiently complicated that they are
>better placed in a special book devoted to that subject (like FTIR
>spectra). AEM analyses are problematical, by no means as useful as
>general EDS spectra from an SEM or EMP, which could be valuable if
>graphical data are included. Beam damage and atom migration are
>potentially a big problem with AEM data, and thickness variations
>(often assumed to be "thin enough" by the original worker) can lead to
>a big change in relative intensities. A good example includes Ti
>oxides, where the Ti absorbs O strongly, sometimes so much that the O
>peak is nearly lost in thicker samples. The apparent presence or
>absence of the lighter elements with EDS analyses on thick samples
>depends on the nature of the detector as well. The REE pattern is by
>no means definitive of a given mineral, controlled as it is by the
>bulk composition of the rock, or by the presence or absence of other
>REEophile minerals. Here one can point to apatite or epidote, which
>in the absence of monazite may show far more LREE than when it is
>present. I would say that the critical measurements are the optical
>data, not even the EMP analyses (not exactly a "bulk measurement" but
>maybe that is what Sengupta meant). The problem of solid solution is
>so great that one could tabulate hundreds or even thousands of
>analyses or XRD patterns for certain rock-forming minerals such as
>garnets, amphiboles, micas, pyroxenes. Perhaps one should include
>analyses when available only if fairly complete optical data are given
>for the same material, but that will tend to be the original
>description of the mineral and not most later work, which typically
>doesn't include optical data. I think that addressing Sengupta's one
>short paragraph substantively means a tremendous amount of work.
>cheers,
>eric
>
>
>On Aug 5, 2008, at 11:43 AM, David Hirsch wrote:
>
>> Sorry for the mass email.
>> -Dave
>>
>> On Aug 5, 2008, at 8:41 AM, David Hirsch wrote:
>>
>>> Dear Dr. Sengupta,
>>> Thanks for the comments and suggestions. Some of these are
>>> already available in Bob Downs' RRUFF IMA database, to which my
>>> system is going to be tied.
>>> -Dave
>>>
>>> On Jul 30, 2008, at 11:32 PM, Pranesh Sengupta wrote:
>>>
>>>> Dear Prof. Hirsch,
>>>>
>>>> First of all I must appreciate the novel attempt you have taken to
>>>> bring all the relevant information on minerals to a single place.
>>>> I feel that the web-site will be more useful if can incorporate
>>>> data obtained from Raman spectroscopy and TEM analyses on each
>>>> mineral together with geochemical data such as REE pattern, bulk
>>>> composition etc, if those are already available.
>>>>
>>>> With bset wishes,
>>>> Pranesh Sengupta
>>>>
>>>> Materials Science Division
>>>> Bhabha Atomic Research Centre,
>>>> Mumbai, India.
>>>>
>>>>
>>>>
>>>> Date: Tue, 29 Jul 2008 10:02:14 -0700
>>>> From: [log in to unmask]
>>>> Subject: Petrography database & search: Call for Comments
>>>> To: [log in to unmask]
>>>>
>>>>
>>>> (apologies for multiple postings)
>>>>
>>>> Petrographers and Mineralogists,
>>>> I plan in the near future to create an online database of mineral
>>>> optical properties under the auspices of the IMA, searchable
>>>> through a custom web interface. At the outset, the data will all
>>>> be from published references, but the database will be editable by
>>>> the community of petrographers, so that it can improve over time.
>>>> Because the core system will be designed in the coming academic
>>>> year (2008-2009), I am calling now for comments on the database
>>>> design and search interface. By offering comments now, prior to
>>>> the initiation of work, you can help this facility be more useful
>>>> for your professional work, research, and teaching.
>>>>
>>>> A great deal more information, including a timeline, database
>>>> fields, and a mock-up of the interface, is available here:
>>>> http://almandine.geol.wwu.edu/~dave/petsearch/
>>>>
>>>> I hope you are willing to take a moment to examine this and
>>>> consider whether the design is optimal for your use. Furthermore,
>>>> I hope you will offer comments as to whether and how such a
>>>> facility would be useful for you (such comments might be used in
>>>> funding requests).
>>>> Thanks,
>>>> Dave
>>>>
>>>> ============================
>>>> Dave Hirsch
>>>> Associate Professor
>>>> Department of Geology
>>>> Western Washington University
>>>> persistent email: [log in to unmask]
>>>> http://www.davehirsch.com
>>>> voice: (360) 650-2166
>>>> aim: [log in to unmask]
>>>> vCard: http://almandine.geol.wwu.edu/~dave/personal/DaveHirsch.vcf
>>>> ============================
>>>>
>>>>
>>>>
>>>>
>>>> Explore the seven wonders of the world Learn more!
>>>
>>>
>>> ============================
>>> Dave Hirsch
>>> Associate Professor
>>> Department of Geology
>>> Western Washington University
>>> persistent email: [log in to unmask]
>>> http://www.davehirsch.com
>>> voice: (360) 650-2166
>>> aim: [log in to unmask]
>>> vCard: http://almandine.geol.wwu.edu/~dave/personal/DaveHirsch.vcf
>>> ============================
>>>
>>>
>>>
>>
>>
>> ============================
>> Dave Hirsch
>> Associate Professor
>> Department of Geology
>> Western Washington University
>> persistent email: [log in to unmask]
>> http://www.davehirsch.com
>> voice: (360) 650-2166
>> aim: [log in to unmask]
>> vCard: http://almandine.geol.wwu.edu/~dave/personal/DaveHirsch.vcf
>> ============================
>>
>>
>
>
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