Pine Country Gem & Mineral Society

HAPPY NEW YEAR!

Wow! 2015! It is hard to believe that we are in a new year already.  Time really does fly when you are having fun.  It also flies when there is a lot of work going on.  This coming year will probably be no exception. I look forward to serving as the new president of our Pine Country Gen and Mineral Society.  There are many things that we can do to promote and build up on club.  I will be asking for assistance from many of you as needs arise.  We need to make some more progress on our club house to get the workshop functional.  The newly formed Junior Rock Club is up and going with some very excited students that are eager to learn about rocks and minerals.  I hope that each of you will consider taking on a mentoring role to these students and pass on the knowledge to the next generation.  I foresee a great year for our club, and look forward to working with each of you.

Michelle Talcott

Looks like we didn't have to wait long for winter to get here because it is cold outside today.  Just a short letter for everyone to let them know about next week's meeting.  Even though we have just completed the national elections, we still have some club elections coming up this next meeting.  We will elect the President, Vice President, Secretary, and Treasurer for the coming year.  The nominating committee will meet sometime before our Thursday meeting to compile a list of nominees for the positions for 2015.  Make sure you come to the meeting, because sometimes folks get elected to these positions by acclamation.  Think we would not do something like that, think again.  Along with that, if you have any suggestions for nominees, we will be glad to add them to the list, just contact me.

Also, our "Rock Hound of the Year" nominee will be chosen at the next meeting.  Please in 50 words or less define your choice for this prestigious award in our club for the year.

This will be our last official club meeting of the year followed by our Christmas Party in December.  See you this coming Thursday night.

Bill

PRESIDENT’S MESSAGE

All I got to say is the annual show was a success……. thanks to everyone
who contributed and spent the time making sure everything and everyone
was felt welcomed. I think that this is the first show I have been part of
that the majority of club members showed the interest and participated in
all aspects of putting this thing together. We had a great crew that was
eager to fill in when someone needed a break and do what was necessary.
I know that Ann as show chairperson appreciated it and I as president
appreciated it. I was especially proud that most all of our newest
members were present and willing to do a job or any job.
This is what it takes to make events such as this a success. I know our
vendors could see the work put into this show and this is what makes
them want to come back each year.
Thanks again to everyone.

Bill Talcott

Bornite or Peacock Ore and Chalcocite

by: Jody Dorman, member PCGMS

Bornite: one of nature's most colorful minerals.
Bornite, which is a copper iron sulfide, and a major
ore of copper, can show beautiful colors such as
purple, blue, and red which is why it is called Peacock
Ore. Bornite's name is from the Austrian discoverer
mineralogist Ignaz Von Born. Bornite crystals
are relatively common, but when found they are
pseudocubic, dodecahedral, or octahedral, frequently
with curved or roughed faces. Although
Bornite is more often compact, granular, or massive,
its colors can be coppery red, coppery brown,
or bronze. Bornite frequently changes upon weathering
to chalcocite. Chalcocite is one of the most
important ores of copper. Chalcocite is usually
massive but on rare occasions, it occurs in short
prismatic or tubular crystals or as pseudohexagonal
prisms formed by twinning. The name chalcocite is
derived from the greek word for copper. Chalcocite
belongs to a group of sulfide minerals formed at
relatively low temperatures as alteration products of
other copper minerals, such as Bornite . These alteration
zones are often hydrothermal veins with
minerals such as Bornite, Quartz, Calcite, Covellite,
Chalcopyrite, Galena, and Sphalerite in addition to
chalcocite. Bornite major deposits occur in Tasmania,
Chile, Peru, Canada, and the United States.
Chalcocite's valuable ore deposits occur in the US
in Ely, Nevada ,and Morenci, Arizona, and Butte,
Montana and excellent crystals are found in Bristol,
Connecticut. and are also found in Australia, Chile,
the Czech Republic, Norway, Peru, Russia, and
Spain.

source is Smithsonian Rock and Gem book

WHAT IS HARDER THAN DIAMOND?— HIGH-TECH DIAMOND!
Zeb William Rike III

To See Diagrams and Charts Associated with this Article

Refer To July 2013 Pineywoods Rooter

COMPOSITION O F D I A M O N D

We are all familiar with the fact that diamonds
are pure carbon, the hardest of several allotropic
forms. (*) It is interesting that the hardest and softest
minerals are both crystalline forms of carbon.
Atomic structure of both diamond and graphite are
shown for comparison. Diamonds crystallize in the
cubic crystal form. The carbon atoms are shown for
one diamond unit cell.
In Diamond, every carbon atom is covalently
bonded to four others at corners of a regular
tetrahedron. Angle between any two atoms in the
tetrahedron is 109o 28’. (*) The covalent bonding
extends indefinitely in all directions, to the outer
surfaces of the diamond crystal where each carbon
is bonded to hydrogen or oxygen. (*) (1-4)

To See Diagrams Refer To July 2013 Pineywoods Rooter

GRAPHITE

We will mention in passing that the structure of
graphite has stacked sheets of hexagonally bonded
carbon atoms with no bonding between the sheets
and it crystallizes in the hexagonal crystal system.
The slipping of the sheets accounts for the softness
and lubricity of graphite. (5)

H A R D N E S S O F D I A M O N D (6-9)

Diamond is hard because of the strength of the
covalent bonds throughout the crystal; any diamond
is, in effect, a single molecule. Imperfections in the
crystal lattice give a small degree of reduction of
hardness. Diamonds are so hard that our familiar
Moh’s hardness scale (based on scratching one mineral
with another) is insufficient to show relative
hardness. There are other hardness scales which depend
on measuring the size of an indentation of a diamond
tip (under standard conditions) in the sample
of interest. There is a way larger difference in Knoop
indentation hardness between Moh’s 9 and 10 than
between 8 and 9. These scales can distinguish relative
hardness of the ultra-hard, such as showing that
some crystallographic planes in a diamond crystal are
considerably harder than others. However, the indentation
tip has to be made of the harder material;
natural diamond will not indent the harder forms.
Nano-diamond aggregates are harder than diamond;
testing with a nano-diamond tip shows that a surface
perpendicular to the [111] crystallographic direction                                                                                                                                  

has a hardness of 167oGPa while the nano-diamond

tip has hardness of 310oGPa. It is very hard to find

numerical statements of hardness for the ultra-hard
materials. Some crystal faces in the diamond are
100X harder than others. (3)

Natural diamond is about 98.98% 12C and about
1.02% 13C. Since 13C is about 8% more massive
than 12C and makes slightly shorter bonds, each
atom of 13C is a slight crystal defect. It is possible
(but quite costly) to separate the 12C and 13C to enable
synthesis of diamond from either. (*) It has
been postulated that isotopically pure diamond
would be harder than natural diamond because of
the reduction in crystal defects. This has been confirmed
with 12C diamond and taken advantage of in
diamond anvil high pressure cells(*) which can
achieve pressures greater than at the center of the
earth. (5)
12C diamond is more easily made than the
13C diamond because of the greater abundance of
the lighter isotope. Pure 13C diamond would be
considerably harder yet because of the shorter
bonds and higher density.

YET HARDER MATERIALS

On theoretical grounds, it has been calculated
that the cubic modification of boron nitride could
be as hard as diamond and the so-far hypothetical
material beta-carbon nitride may be harder than diamond
in some forms “Keep tuned right here”.

FOOTNOTES

1. (*) I have starred items that could easily be
expanded to result in a two or more page article
for The Bulletin. And research for any
one of these would suggest other topics for
articles.

2. http://en.wikipedia.o r g / w i k i / D i a m o n d

3. h t t p : / / e n . w i k i p e d i a . o r g / w i k i / M a t e -
r i a l _ p r o p e r t i e s _ o f _ d i a m o n d

4. h t t p : / / e n . w i k i p e d i a . o r g / w i k i / I s o t o p i -
c a l l y _ p u r e _ d i a m o n d

5. h t t p : / / e n . w i k i p e d i a . o r g / w i k i / G r a p h i t e

6. h t t p : / / w w w . g o o g l e . c o m / p a t e n t s / U S 5 2 9 5 4 0 2

7. h t t p : / / b o o k s . g o o g l e . c o m / b o o k s ? i d = g W g -
r c h M 7 0 0 C & p g = P A 1 2 9 1 & l p g = P A 1 2 9 1 & d q
= h a r d n e s s + o f + i s o t o p i c a l l y + p u r e + d i a m o n d &
s o u r c e = b l & o t s = x H J 8 s F U B q i & s i g = T I z L p e s
6 g b 3 8 4 N U -
v k c C e l c 8 D W Y & h l = e n & s a = X & e i = T E T S U f
r g O O T B 0 A H 4 t Y D Y C Q & v e d = 0 C E U Q 6 A E
w B Q # v = o n e p a g e & q = h a r d n e s s % 2 0 o f % 2 0 i s
o t o p i c a l l y % 2 0 p u r e % 2 0 d i a m o n d & f = f a l s e

8. h t t p : / / e n . w i k i p e d i a . o r g / w i k i / I s o -
t o p e s _ o f _ c a r b o n

9. h t t p : / / e n . w i k i p e d i a . o r g / w i k i /
K n o o p _ h a r d n e s s _ t e s t

XENOTIME

Jody Dorman, member PCGMS

June 2013

Xenotime is Yttrium Phosphate. It takes its name
from the Greek for "vain honor", because the yttrium
in xenotime was mistakenly believed to be a new element
when it was described in 1832 .

It is found as glassy, short to long prismatic crystals, or as rosette -
shaped crystal aggregates. It's color can be yellowish to
reddish - brown, fleshy red, grayish - white, or
pale to wine - yellow .

Xenotime occurs as an accessory mineral in igneous rocks and in associated pegmatites,                                        where it can form large crystals.

It also occurs in quartz rose and micaceous gneisses , and often
found with zircon, anatase, rutile, sillimanite,
columbite, monazite, and ilmenite. It is widely distributed,
with notable occurrences in Japan, Sweden,
Norway, Germany, Brazil, Madagascar, and in the
US, New York, North Carolina, and Colorado . Garnet
containing yttrium is used to make lasers. Mirrors
change the directions of the beam, which is colored
by dyes and filters. Red yttrium phosphors are used
in the color TV screens. Xenotime forms a solid solution
series with chemovite -[Y] [YAs04] and,
therefore, may contain trace of impurities of arsenic,
as well as silicon dioxide and calcium .

The rare earths dysprosium, erbium, terbium, and ytterbium,
and metal elements like thorium and uranium [all replacing
yttrium] are the expressive secondary components
of xenotime. Due to uranium and thorium impurities,
some xenotime specimens may be weakly to
strongly radioactive, so be careful .

Properties

Group : Phosphate
Crystal System : Tetragonal
Composition : YPO6
Hardness : 4 - 5
Cleavage : Perfect
Luster : Vitreous to Resinous
Streak : Pale brown or reddish
Gravity : 4.4 - 5.1
Transparency : Transparent to Opaque

Source:

Wikipedia and Smithsonian Rock and Gem Book