www.cochisecountyrock.org
“Finding and
Grinding Rocks in
June 2007
This issue edited by Paul
McKnight
_________________________________________________________________
If you have not yet signed up, please call Hanni at
520-826-1009 by June 10. Both Eurofresh
and the Forest Service need to know the number of attendees in advance.
Date: Saturday, June 16
9:15 am: Meet
at Willcox Safeway parking lot, leave at 9:30
10 to
11:30: Tour organized by Henry Vandenbos
(If only
attending picnic, join the group at 11:30 at Eurofresh)
11:30 to
Noon: Travel to
Noon to 2
pm: 40th Annual Picnic
The
picnic area is at 5300 ft. elevation with shade trees, picnic tables and
toilets, but no water. Meat (bratwurst), plates, and silverware will be
provided.
Sigels
and Pontious will bring grills for cooking.
Last
names beginning with
A thru H
bring a salad
I to O
bring a covered dish
P thru Z bring
dessert
Food
Safety: Please plan to keep your food
cool for several hours while your car is sitting in the sun at Safeway and
Eurofresh.
Non-member
guests are welcome as long as Hanni is notified in advance. Guests must join the club for a day (cost $1)
and sign a risk disclosure / release.
Our next meeting will be Monday,
September 10 at 7 pm at the
About
12 cars met the landowner Mr. Marcos on
May 14, 2007
President Paul McKnight called the
meeting to order.
There were no new members or
visitors. Dick Yeager made a motion to accept the published minutes for
the previous meeting. Ilse Edgett
seconded the motion. Motion carried. Walter gave the treasurer’s
report. Paul then explained that we had made the mistake of paying the
dues for the Sunsites Chamber of Commerce thinking they were the Sunsites
Community Assoc. dues. The membership now needs to approve the expense
since it was not in the budget. Dick made a motion to approve that
expense. Larry seconded the motion. Motion carried.
Paul gave
some announcements concerning our members. Ed Francis from
Irvin
reported that lapidary classes would continue on Monday afternoons ONLY if you
call him by Sunday evening the day before. Most of the attendees are
leaving for the winter.
Bob Fenner gave us information on the upcoming field trip. He reminded us
to bring hammers, chisels, etc. Also high clearance vehicles needed, no
cars. This site was once a working Fluoride mine. Vandalism has
stopped further production. The owner would consider hearing of any
interest in a possible reclamation project. We will meet on
Hanni gave us the report for the picnic scheduled for June 16.
We will be lead on a tour of
Eurofresh thanks to Henri Vandenbos. We will then go to a picnic area
near
Those with names ending in A-H
bring a salad, I-O covered dish, and P-Z bring desert. We will meet at
Willcox Safeway at 9:15a.m. We will leave at 9:30 to arrive at Eurofresh
at 10a.m.
There are
separate sign-up sheets for tour and picnic if members only want to attend one
or the other. There are also sign-up sheets for the field trip and
hospitality for the fall.
The meeting was adjourned for intermission. During intermission raffle
tickets may be purchased. The raffle will be held at the end of
intermission. We will reconvene at 7:40 for our speaker John Ware from
Amerind.
Respectfully,
Carol A. Pontious
Secretary
Interested in
lapidary? Irvin Pontious will conduct
Lapidary sessions during the summer on an as needed basis. Call him at 824-0110.
7 Board meeting 7 pm
16 40th annual
Picnic and Eurofresh Tour
Field Trip
Field Trip
30 Board Meeting
10 Regular Meeting – Host
Ilse-Rose Edgett
15 Field Trip
27 Board Meeting
8 Regular Meeting
14 Field Trip
1 Board Meeting
12 Regular Meeting
17 Field Trip
29 Board Meeting
17 Christmas Party
Upcoming
Regional Events
June 7-10, 2007. Rocky Mountain Federation
Annual Convention & Show.
June 15 -17 (but remember our June 16 picnic) Tombstone Gem Show at the Holiday
Inn on Highway 80
August 25-September 3 Agate 2007,
October 6-7, 2007 Phelps Dodge Annual Turquoise Hunt, Bisbee Mining and
October 11-13, 2007 21st Annual Quartz Crystal Dig,
October 13-14, 2007 Huachuca Gem
& Mineral Show, Elks Lodge,
President Paul McKnight 520 824-4054
Vice-President Jack Weller 520-826-0625
Secretary Carol Pontious 520 824-0110
Treasurer Walt Sigel 520-826-1009
Delegate at Large Jack Light 520-384-4774
Hospitality
Coordinator Hanni Sigel 520-826-1009
Dues are due. $10 for individual and $20 for family. Please mail your check to Sunsites Gem &
Mineral Club,
Metamorphic Rocks
Metamorphic rocks are formed when a pre-existing rock type (the protolith) is changed by great heat and pressure inside the earth. Think of metamorphic rocks as recycled rocks. When igneous, sedimentary, or even metamorphic rocks get buried deep beneath the surface of the earth, over millions of years, the heat and pressure inside the earth change them into something else. Limestone can be changed into Marble, Sandstone can be changed into Quartzite, and Shale can be changed into Slate.
The change in the particle size of the rock during the process of metamorphism is called re-crystallization. For instance, the small calcite crystals in the sedimentary rock Limestone change into larger crystals in the metamorphic rock Marble. In metamorphosed Sandstone, re-crystallisation of the original quartz sand grains results in very compact Quartzite, in which the often larger Quartz crystals are interlocked.
Metasomatism is the
drastic change in the bulk chemical composition of a rock that often occurs
during the processes of metamorphism. It is due to the introduction of
chemicals from other surrounding rocks. Water may transport these chemicals
rapidly over great distances. Because of the role played by water, metamorphic
rocks generally contain many elements that were absent from the original rock,
and lack some which were originally present. Still, the introduction of new
chemicals is not necessary for re-crystallization to occur.
Contact metamorphism is the name given
to the changes that take place when magma is injected into the surrounding
solid rock (country rock). The changes that occur are greatest wherever the
magma comes into contact with the rock because the temperatures are highest at
this boundary and decrease with distance from it. Around the igneous rock that
forms from the cooling magma is a metamorphosed zone called a contact
metamorphism aureole. Aureoles may show all degrees of metamorphism from
the contact area to unmetamorphosed (unchanged) country rock some distance away.
The formation of important ore minerals may occur by the process of
metasomatism at or near the contact zone.
Source: Rockhound Ramblings – February 2006
via ROCK CHIPS – April
2006
with some additional cut
and paste from Wikipedia.