GEOS 3010 University of Maine Silicate Minerals and Phase Diagrams Worksheet

GEOS 3010
In-Class Activity #6
Silicate Minerals
Answer the following in groups and turn in one per group:
1. Two chemical analyses for a silicate mineral are provided.
a. Calculate the oxide proportions (OP) for each sample (in the table).
b. Write a general formula for this mineral group.
c. Determine the silicate mineral group and subclass to which these samples belong.
d. Write a specific chemical formula for each analysis.
2. Using the olivine T-X phase diagram:
a. Determine the coexisting mineral and liquid compositions at 1350°C.
b. A liquid of composition 80% Fo begins to crystallize. Using the diagram, determine (1) the
temperature at which the first mineral forms and (2) the composition of the mineral that
coexists with this liquid.
c. A mineral of composition 35% Fa heats up and begins to melt. Using the diagram,
determine (1) the temperature at which melting begins, and (2) the composition of the
liquid that coexists with this mineral.
GEOS 3010
In-Class Activity #6
Silicate Minerals
1. Mineral Analyses. Below are chemical analyses of two mineral samples of the same group:
(oxide wt%)
(oxide wt%)
a. Which elements in this mineral are likely to share solid solution? Why?
b. In the first column of the table below, calculate the atomic weight of each oxide.
Example: SiO2 = 28.08 gm/mole Si + 2(16.0) gm/mole O = 60.08 gm/mole SiO2
In the next two columns, calculate the proportions of each oxide (OP) in this mineral by dividing
the oxide wt% (in the table above) by the atomic weight of each oxide.
Example: Sample #1 SiO2 = 58.49 gm / 60.08 g/mol = .973 mol
Finally, sum the proportions of all of the oxides except silica.
Oxide atomic weight
Total metal oxides
(add all but SiO2)
OP (moles)
OP (moles)
c. What is the ratio of total metal oxides to SiO2 for each sample in this mineral group?
d. Write a general formula for this mineral group. [HINT: group the solid solution elements
together, add Si, then count up the oxygen and move these to the end of the formula.]
e. Look carefully at the elements making up this mineral, the ratio of metal oxides to SiO2, and the
ratio of Si to O. What silicate subclass and mineral group do these samples belong to?
f. We are almost ready to write a specific (exact) formula for each sample of this mineral. But since
the cation (metal) proportions do not exactly add up to 100%, we have to do a little math-magic
to normalize the proportions in order to write the formula. Let’s also ignore Mn, since it is

Don't use plagiarized sources. Get Your Custom Essay on
GEOS 3010 University of Maine Silicate Minerals and Phase Diagrams Worksheet
Just from $13/Page
Order Essay
Calculate the price
Make an order in advance and get the best price
Pages (550 words)
*Price with a welcome 15% discount applied.
Pro tip: If you want to save more money and pay the lowest price, you need to set a more extended deadline.
We know how difficult it is to be a student these days. That's why our prices are one of the most affordable on the market, and there are no hidden fees.

Instead, we offer bonuses, discounts, and free services to make your experience outstanding.
How it works
Receive a 100% original paper that will pass Turnitin from a top essay writing service
step 1
Upload your instructions
Fill out the order form and provide paper details. You can even attach screenshots or add additional instructions later. If something is not clear or missing, the writer will contact you for clarification.
Pro service tips
How to get the most out of your experience with Writall
One writer throughout the entire course
If you like the writer, you can hire them again. Just copy & paste their ID on the order form ("Preferred Writer's ID" field). This way, your vocabulary will be uniform, and the writer will be aware of your needs.
The same paper from different writers
You can order essay or any other work from two different writers to choose the best one or give another version to a friend. This can be done through the add-on "Same paper from another writer."
Copy of sources used by the writer
Our college essay writers work with ScienceDirect and other databases. They can send you articles or materials used in PDF or through screenshots. Just tick the "Copy of sources" field on the order form.
See why 20k+ students have chosen us as their sole writing assistance provider
Check out the latest reviews and opinions submitted by real customers worldwide and make an informed decision.
Public Relations (PR)
Thank you
Customer 454893, September 9th, 2022
Health Care
I got an A and got a good feedback from the instructor. Thanks
Customer 453877, May 20th, 2020
Very Well structured essay and On-time!
Customer 455059, November 3rd, 2021
Great paper and done before the deadline. Thank you
Customer 454659, October 20th, 2021
Cyber Warfare
Got a 94% thank you!
Customer 452961, August 8th, 2021
You have done it again!! Thanks for the excellent paper,,, the writer know what they are doing and knows how to follow instructions!
Customer 454497, January 17th, 2021
I got a B thanks
Customer 453877, February 1st, 2021
Best writer ever
Customer 454983, February 21st, 2022
Thank you!
Customer 454959, February 6th, 2022
Amazing work!
Customer 454937, October 7th, 2021
Customer 453877, March 7th, 2020
Great content, resources, and turn around!
Customer 454991, November 2nd, 2021
Customer reviews in total
Current satisfaction rate
3 pages
Average paper length
Customers referred by a friend
15% OFF your first order
Use a coupon FIRST15 and enjoy expert help with any task at the most affordable price.
Claim my 15% OFF Order in Chat
Live Chat+1(978) 822-0999EmailWhatsApp

Order your essay today and save 20% with the discount code GOLDEN