November 2008 Mineral of the Month: MALACHITE

Hello All Del-Airs and Interested Guests!

Welcome to the online version of our November 2008 Mineral of the Month:

MALACHITE


Malachite is a green mineral with a widely variable habit. Typically it is found as crystalline aggregates or crusts, often banded in appearance, like agates. It is also often found as botryoidal clusters of radiating crystals and as stalactitic aggregates as well. Single crystals and clusters of distinguishable crystals are very uncommon, but when found, they are typically acicular to prismatic. It is found in the oxidized regions of copper deposits. It is also frequently found as a pseudomorph after Azurite crystals. It's chemical properities are as follows:

Crystal Structure: Monoclinic; Mineral Group: Carbonates; Chemical Formula: Cu2[(OH)2ICO3]; Specific Gravity: 4.0; Tenacity: Brittle; Color: Rich Green; Hardness: 3-1/2 to 4; Luster: Adamantine/Vitreous on Crystal Faces. Silky on Fibrous & Botryoidal Habits; Transparency: Translucent to Opaque; Streak: Pale Green; Cleavage: Perfect; Fracture: Irregular/Uneven, Sub-Conchoidal, Fibrous

October 2008 Mineral of the Month

October 2008 Mineral of the Month:

Barite

Named from the Greek word βάρος, meaning weight, due to its unusual heaviness for a non-metallic mineral. Barite forms as tabular and prismatic crystals which can be very large. It also forms as small sand bearing rose shaped concretions called desert roses. Other habits are granular, fibrous, cockscomb, or columnar. It forms in hydrothermal veins with a number of other minerals including quartz, calcite, fluorite, galena and many others. Barite also forms in clay nodules, in veins of sedimentary strata and around hot springs. It is insoluble in acids and some varieties are fluorescent.

Its chemical properties are as follows:

Crystal Structure…Orthorhombic
Mineral Group...Sulfates

Chemical formula...BaSO4)

Specific Gravity...4.5

Tenacity…Brittle

Color...Colorless, White, Gray, Red, Green, Brown, Blue, Yellow

Hardness...3 to 3-1/2
Luster...Vitreous, Resinous or Pearly
Transparency...Transparent to Translucent
Streak…White
Cleavage...Perfect
Fracture…Uneven

Tri-Fecta At The Antelope Valley Fair

Kudos' to Del Air members Richard Haering, Chris Ward and Bob Knox for continuing their first place winning streak with their display cases at the 70th Annual Antelope Valley Fair.

This is Richard Haering's first year submitting a competitive case. His display of metamorphic rock slices has won first place in both the CFMS and Antelope Valley Fair shows. Way to go Richard!!! In addition to winning the first place prize in each of their respective classes, Chris Ward was also awarded the "Judges Choice" prize for his display of world-wide geodes and Bob Knox walked off with the esteemed "Best in Show" prize for his display of incredible Stromatolites.

We also have our Del Air club case on display as well.

The fair is open daily and runs thru Monday September 1st, 2008. I encourage all to attend if you can. It is a lot of fun and educational as well.

See You All At The September Meeting!!

August/September 2008 Mineral of the Month

August/September 2008 Mineral of the Month:




Quartz

Quartz is the most common mineral found on the surface of the Earth. A significant component of many igneous, metamorphic and sedimentary rocks, this natural form of silicon dioxide is found in an impressive range of varieties and colors. There are many names for different varieties: Crypto-crystalline varieties of Quartz are called Chalcedony and include the Agate family. Quartz can also be found in other forms such as Petrified Wood and Jasper.

Its chemical properties are as follows:

Crystal Structure…Trigonal

Mineral Group...Oxides

Chemical formula... SiO₂

Specific Gravity...2.65

Tenacity…Brittle

Color...Colorless, Purple, Rose, Black, Yellow, Brown, Green, Orange, etc.

Hardness...7
Luster...Vitreous
Transparency...Transparent to Translucent
Streak…White
Cleavage...Poor/Indistinct
Fracture…Conchoidal

Prasiolite, Tigers Eye, Citrine and Onyx are also forms of Quartz. Pure quartz is colorless or white; colored varieties include rose quartz, amethyst, smoky quartz, milky quartz, and others. The most important distinction between the types of quartz is that of macro-crystalline (individual crystals visible to the unaided eye) and the crypto-crystalline varieties (aggregates of crystals visible only under high magnification). Chalcedony is a generic term for crypto-crystalline quartz. The crypto-crystalline varieties are either translucent or mostly opaque, while the transparent varieties tend to be macro-crystalline. Although many of the varietal names historically arose from the color of the mineral, current scientific naming schemes refer primarily to the microstructure of the mineral. Color is a secondary identifier for the crypto-crystalline minerals, although it is a primary identifier for the macro-crystalline varieties. However this does not always hold true.

Antelope Valley Fair

To All Del Air Members and Interested Guests:

This is a reminder that myself, Bob Knox and Richard Haering will be entering 4 competitive cases in the Antelope Valley Fair this year. One of these cases will be a club case and this will be the first time that the Del Air's have been represented at this fair. This is the 70th Annual celebration of this fair and I have been a competitive displayer here for the past four years. I encourage all to attend as I feel it is the best fair around. Smaller than the LA County Fair and larger than the Ventura County Fair, the Antelope Valley fair has something for everyone.

I realize everyone must thinking its too hot or too far away but it really is no farther than the Ventura fair and to beat the heat, each year, I arrive around 5:30 pm as the fair is open till midnight. I first check out all the attractions and displays in the air conditioned buildings and by the time I am through, the sun has gone down and the breeze has kicked in and the desert evening turns out to be quite enjoyable and comfortable.

The fair is located at the new Antelope Valley Fairgrounds:
2551 West Avenue H, Lancaster, CA 93536
661-948-6060
Take the I-14 freeway north to Avenue H exit and turn left. You can't miss it.

The Antelope Valley Fair is open this year from Friday August 22nd through Monday September 1st 2008. They are open from 12 noon till midnight on the weekends and from 4:00 pm till midnight midweek.

Admission is:
$8.00 for adults 12 yrs and older
$5.00 for juniors 6 to 11 yrs and seniors 62 yrs and above
$Free for children under 6 with paid adult and for active military with military ID

Parking is $5.00

So join us at the fair and check out our Rock and Gem exhibits as well as everything else the fair has to offer. Hope to see you there!!

CORRECTION TO THE GARAGE SALE DATES

Thanks to our very own eagle eyed Del Air member, Ethel Hellenthal , it has been brought to my attention that I listed the tentative date for the upcoming annual Del Air garage sale incorrectly. The correct tentative date is Saturday September 20th, 2008. I originally posted the date as being in November. I apologize for this error and hope you all will forgive me! If you scroll down to that post you will see that it has been corrected.

Your humble blogger,
Chris.

August /September 2008 Mineral of the Month

Just because the Del Airs do not have any regularly scheduled meetings during the month of August doesn't mean we have forgotten the Mineral of the Month!

This new club feature has proven to be such a hit each month that we have decided to do a double presentation at our September 4th 2008 meeting.

The featured mineral will be........'Quartz'.........in all its spectacular forms and brilliant colors and exotic crystal shapes. Amethyst, Citrine, Jasper, Agate, Chalcedony, etc, etc, etc,

There will be a double sided full color handout for all to take home. As always, we encourage all attendees to bring their most prized quartz specimens to the September 4th 2008 meeting to share with the club. Lets make this our biggest turnout yet.

So keep an eye on our blog. Coming soon.....to a PC or laptop near you.....

The August/September 2008 Mineral of the Month.....'Quartz'

Annual Del Air Rockhounds Garage Sale and Grab Bag Stuffing Extravaganza

Attention all Del Air Members and Interested Guests:

First, the garage sale....

Just a heads up to let you all know we have tentatively scheduled our annual garage sale for Saturday September 20th 2008 starting @ 9:00 am to be held at Bob Backus's home. Should this change for any reason a new post will be sent to all.

If you have anything you'd like to donate to the sale or if you'd like to donate your time and help out during the sale please contact Bob Backus (his contact information can be found in the monthly bulletin) or you can e-mail me @ chris_ward678@yahoo.com and I will respond with the appropriate information.

All proceeds go to the Del Air Rockhounds and help to bring us closer to obtaining our own shop.

Second, the Grab Bag Stuffing Extravaganza.....

Bob and Maxine Dearborn will be hosting a grab bag stuffing at their home tentatively scheduled for Saturday November 8th 2008 at 10:00 am. Again, should this change a new post will be sent to all.

We have gone thru almost all of our inventory of grab bags. As you may or may not know, the grab bags are the number one selling item at our annual show as well as the many school fairs our club is involved with each year. Our show is quickly approaching and we need to replenish our stock. Should you care to volunteer your time, usually 2 or 3 hours, please contact Bob or Maxine (their contact information can also be found in the monthly bulletin ) or e-mail me at the above listed e-mail address and I will respond appropriately.

Thank you all in advance for your participation and support.

Information On DEL AIR Education Team

The Del Air Rockhounds Club Presents............

"ROCKS IN YOUR CLASSROOM"
Del Air Rockhounds club members can visit your classroom with a presentation on geology and the earth sciences. Our education outreach committee offers a variety of classroom programs.

• Introduction to Geology (4th grade curriculum) Interactive Discussion / Slide Show / Hands-on Specimens

Students will have a chance to hold a variety of rocks and fossils in their own hands! Program is 50 minutes to an hour depending on age level

• Introduction to Fossils (2nd grade curriculum) Interactive Discussion / Hands-on Specimens / Project Stations

Students will have the chance to hold many types of fossils in their own hands such as Petrification, Trace, Amber, and Frozen fossils. Program is 40 minutes to an hour depending on age level. To schedule you school visit contact: Del Air Member Maxine Dearborn at our Voice Mail: (818) 714-0321 Programs are free of charge! (nominal transportation fee outside of the San Fernando Valley) Donations may be given to Del Air Rockhounds Club. Please scroll down to see what some of our star students have to say about our "Rocks in Your Classroom" presentations.......

2008 C.F.M.S. Show Report

Greetings to all Del Air members and interested guests!

It turned out to be a banner year for Del Air members at the 2008 C.F.M.S show at the Ventura County Fairgrounds this past weekend. Member Richard Haering took the Blue Ribbon First Place Award in the novice category for his exemplary display of Australian Metamorphic Rock.

Del Air's very own treasurer, Bob Knox, took First Place in the advanced fossils category and was awarded the Blue Ribbon and a plaque for his wonderful collection of Stromatolites.


















And finally, your humble blogger himself, Chris Ward, took the First Place Blue Ribbon and a plaque for my dispaly of Fortification Agates.


















We also displayed a Del Air Club Case at the show. The club cases were for display only and not in a judging category, but if they were, I bet we would have taken a First Place Blue Ribbon for this case as well.


















The three of us attended the awards banquet on Saturday night after the show closed for the day. We had a delicious prime rib dinner with garden vegetables and roasted baby red potatoes with rosemary. Cheesecake and coffee was served for dessert and good time was had by all those in attendance. We made many new friends and got reaquainted with some old ones.


















The weather was incredible with highs in the upper 70's and a cool and refreshing ocean breeze. Foot traffic was much improved over last years show in Lancaster. We volunteered to work in the kids booth on Sunday manning the Spin-a-Wheel, sand sifting for treasure, paint a fossil dinosaur bone and other fun games for the kids. We ran into Del Air members Bob and Maxine Dearborn who showed up on Saturday and also volunteered to work in the kids booth. We saw Jason Badgely, Oscar and Julie Marin and Bob, Leilani, and Jamie Backus as well.









Our heartfelt thanks to those who were able to come out and support the Del-Air's in their quest for victory. And a very special thank you to Bob Backus for his amazing carpentry work on the cases. It took a lot of planning and some good old fashioned knuckle busting to pull off four cases for this show but it was worth every effort and speaking on behalf of all three of us, we are already planning for next years C.F.M.S. show in San Jose. Del Air's ROCK!!

See you all at the July 10th meeting.

Chris, Richard and Bob

July 2008 Mineral of the Month: Gypsum

July 2008 Mineral of the Month

Gypsum

Named in antiquity from the Greek word "gypsos," meaning plaster. It can be found as a massive material including the Alabaster variety and also as clear crystals in the Selenite variety. It can also form as a parallel fibrous growth known as the Satin Spar variety. Commonest of the sulphate minerals, gypsum is found in marine evaporates, in caves where the air is dry enough to allow it to be deposited and remain, at fumaroles, and, on occasion, in the oxidized zones of sulfide deposits. Crystals are tabular and diamond shaped. Rosette shaped masses are known as Desert Roses and radiating forms are termed Daisy Gypsum.

Its chemical properties are as follows:

Crystal Structure…Monoclinic
Mineral Group...Sulfates
Chemical formula...Ca(SO4) . 2H2O
Specific Gravity...2.32
Tenacity…Brittle
Color...Colorless, White, Gray, Reddish, Greenish, Brownish, Yellowish
Hardness...2
Luster...Vitreous (Pearly on cleavage)
Transparency...Transparent to Opaque
Streak...White
Cleavage...Perfect
Fracture...Splintery

Because You Asked

Del Air member Dodd Roth asks:

Do you know of any gypsum mines that have colored rocks?

"Because You Asked" answers:

None that I know of personally, however, there are literally thousands of gypsum deposits around the world...stretching from Antarctica to the Siberian Steeps. Few are mined for anything other than industrial purposes but some collector specimens seem to be collected at a high percentage of them. Though the crystals are colorless to white, many deposits will have mineral associations that can color gypsum in an assortment of shades depending on what the associated minerals are. Mindat.org has a large gallery of gypsum photos from almost 100 locations that show several different colors. Massive forms (lapidary rough) of gypsum can also have a lot of color variation, probably more so than that of crystals. I do not know and can not find a list of commercial gypsum "lapidary material" locations, but If such a list exists it would most likely be a long one.

Thanks for asking!!

"BECAUSE YOU ASKED"

Del-Air guest attendee, Richard Leyton, asks:

I am looking forward to going on the Mt. Gleason field trip on June 21st. The bulletin says to bring light digging tools. What does that mean? A prospector's pick? A gardening trowel? A 6 foot shovel? A full size pick ax?

Thanks, Richard Leyton

'Because You Asked' answers:

Light digging tools would refer to rock hammers, chisels, small garden trowels, crow bars etc. Basically hand sized tools. Also a spray bottle filled with ordinary water to spritz down your specimens to better identify what you are bringing home. Bring a pair of safety goggles to protect your eyes when hammering rocks. I carry one of each of these hand sized tools in a canvas tote bag with handles whenever I go rock hounding. The bag is large enough to hold the rocks I want to bring back as well. A heavy duty back-pack would work too.

Heavy digging tools would refer to full size pick-axes, sledge hammers, full size shovels and industrial size pry bars. These, however, are much more unwieldy and are difficult to lug around especially whens it really hot.

Don't forget to bring food and plenty of drinking water so you stay hydrated. Watch out for snakes and keep an emergency first aid kit in the car.

I hope this answers your question and provides you with a few tips as well.

Till next time...........Happy Rock Hounding!!!

"Because You Asked"

June's mineral of the month, Calcite, elicited a fair amount of oohs and aahs, as members and guests had an opportunity to examine the several beautiful and extremely different examples of this relatively common mineral. Hopefully this new feature of the Del-Air Rockhounds Club is being enjoyed and we are all learning something new.

This brings us to yet another new feature of the club, "Because You Asked". If anyone ever has a question regarding rocks, minerals or other rock hounding subjects that can not be answered while at our monthly meetings, simply e-mail your question to Bob Knox at: rknox1@socal.rr.com or Chris Ward at: chris_ward678@yahoo.com and your query will be researched and answered right here in your blog. Questions may be submitted at any time and members and interested guests will receive an e-mail notification stating the answers have been posted to the blog.

And now....for our first question....

Mrs. Paul O'Connor asks...."In the information handout for the June 2008 Mineral of the Month, Calcite, the word 'gangue' appeared in the mineral's description. What does this word mean?

"Because You Asked" answers:

Ore and Gangue: The general definition of “ore” is a naturally occurring material from which minerals of economic value can be extracted at a profit. For example “gold ore” or “iron ore”. Ore minerals are the specific minerals containing the commodity of interest. Many minerals contain elements of commercial interest, but are not ore minerals because the mineral is “refractory”, meaning it is difficult or impossible to extract the commodity from the mineral. Gangue (pronounced like 'gang') minerals refer to the material so intimately associated with the ore that it has to be mined along with the ore and is later removed by various crushing, grinding and separation processes. The “host rock” is the rock surrounding the ore and gangue, which has no value. To illustrate these relationships, consider the following example for a gold ore:

A gold-bearing quartz vein 1 foot thick occurs in a granite intrusion. The quartz vein contains arsenopyrite and pyrite in addition to native gold. The “ore” in this example is the quartz vein that contains concentrations of gold. The ore mineral is the native gold. The gangue minerals are quartz, arsenopyrite and pyrite. The granite is the host rock.

Thanks for the questions and keep them coming!!

Del Air Rockhounds Present............

June 2008 Mineral of the Month

Calcite

Found in most geologic settings and, in one form or another, as a later forming replacement mineral in many other environments . It is most common as a massive material in limestones and marbles. It forms as chemical sedimentary deposits in limestone and can be regionally metamorphosed into marbles. Calcite is also a common gangue mineral in hydrothermal deposits. Its crystals are rhombohedral and scalenohedral with combinations producing “nailhead” and “dogtooth” forms. Iceland Spar variety shows double refraction. Twinning is very common.

Its chemical properties are as follows:

Mineral Group......................Carbonates
Chemical formula................CaCO3
Specific Gravity...................2.71
Tenacity…………………….Brittle
Color......................................White, Yellow, Red, Orange, Blue, Green, Brown, and Grey
Hardness..............................3
Luster....................................Vitreous, Pearly
Transparency.....................Transparent to Translucent
Streak....................................White to Greyish
Cleavage..............................Perfect
Fracture...............................Subconchoidal

Del Airs Prove To Be Most Popular Once Again!!

The Del Air Rockhounds booth once again proved to be the most popular attraction at the Our Community Charter School's Spring Fair. The day was sunny and bright and not too hot with a nice cool breeze blowing all day long. Del Air members showed up in force to help man the booth. A big and hearty THANK YOU goes out to Bob & Maxine Dearborn, Julie & Oscar Marin, Hiro Matsuo, Len & Ethel Hellenthal, Jeff Dengrove, Bob Knox and Chris Ward. A very special THANK YOU goes out to Ben Fullon and Richard Quezada, two potential new Del Air members, who sacrificed their time to help us out on this event. Ben spent the entire day manning the "What Is It" table helping youngsters and grown-ups alike identify the many amazing rocks we had on display. Richard wasted no time getting down and dirty with the tile saw and in no time was quickly slicing open geodes like a pro. Their participation is greatly appreciated.


















As always, the "Spin-a-Wheel", manned by Ethel, Len and Hiro attracted quite a few people as well as the "Paint Your Own Dinosaur Claw" table expertly handled by Julie, Oscar and Maxine. Bob Knox lent a hand wherever and whenever it was needed. Myself, Jeff, Bob Dearborn and Richard worked the geode cutting table. We all had a blast and ended up raising a goodly amount of money for both the school and our club as well.