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Delvers Gem & Mineral Society, Inc. - mailing address: 3833 San Anseline, Long Beach, CA 90808
DELVINGS The Newsletter of the Delvers Gem & Mineral Society
Volume 74 Number 2 February 2021
The Blues: narrows above a dryfal l , Fal l Canyon, Death Valley – Andrew Hoekstra
DELVINGS February 2021 Page 2
Taps From the Gavel
Hello Members,
Well we are rolling right into the month of February, what happened
to January? It just kinda flew right by. I know our members are itching
to get together and have a meeting which would be great, but even
though the stay at home order is lifted, the infection rates are still
high and it is still advised to not meet in large groups. Hopefully
things will get better soon, and until then, there will be no meeting
the month of February.
I hope you all are getting to work on your rocks with all this stay at
home, whether it be tumbling, cabbing or polishing and all the other
types of lapidary work that can be done. When we do meet again we
should all have some cool things to show.
Take care and stay safe.
Your President,
Marvin Belcher
562-230-9542, [email protected]
Minutes: there was neither a board nor a general meeting during January 2021.
From the Editor’s Desk
This is the 74th issue of the newsletter since I became your editor. For each issue, I try to include
something interesting to read. Since I receive little feedback, neither suggestions nor complaints, I am
unsure what you would like to see. I would really like to include more material from club members.
Your stories and photos are of great interest to other members. It is becoming more difficult to find
anything worth “borrowing” from other newsletters. I am ignorant on most topics, especially lapidary
and jewelry. If I contribute too much, not only will you tire of my favorite subjects, but I will burn-out.
So please consider contributing something - and many thanks to all those who have already done so.
FIELD TRIPS
Field trips remains problematic but some clubs will resume when possible. You might want to bookmark these links for two of the local clubs that welcome non-members on their trips, and revisit their web pages regularly to see if any trips are scheduled take place:
Yucaipa Valley G&MS - https://www.yvgms.org/field-trips?
Searchers G&MS - https://www.searchersrocks.org/next-field-trip
California Federation of Mineralogical Societies Newsletters: https://cfmsinc.org/newsletters/
American Federation of Mineralogical Societies Newsletters: http://www.amfed.org/news/default.htm
2021 Board
President – Marvin Belcher [email protected]
VP – Peter German [email protected]
Treasurer – “Chuck” Pierce [email protected]
Secretary – Judy Belcher [email protected]
Director – Guynell Miller [email protected]
Director – Dale Harwood 310-217-0551
Editor – Andrew Hoekstra [email protected]
DELVINGS February 2021 Page 3
PUBLIC LANDS NEWS – Andrew Hoekstra
San Gabriel Mountains, Southern CA, and Nevada
The National Defense Authorization Act was passed in December over a presidential veto. The House
version of the bill included significant public lands proposals, but these were stripped out of the bill in
conference due to lack of support in the Senate. One section removed was H.R. 2546, the “Protecting
America’s Wilderness Act”, which included expansion of the San Gabriel Mountains National
Monument, creation of a San Gabriel National Recreation Area, and implementation of the Rim of the
Valley Corridor proposal to double the size of the Santa Monica Mountains NRA – these would have
further restricted/prohibited rock hounding. They are all likely to be reintroduced in the new Congress.
H.R. 2546 also included sections affecting public lands in other states, and S. 823, regarding Colorado,
was also omitted from the final bill. Congress rejected the military’s proposal to take-over more public
land in Nevada, including more than a million acres of the Desert National Wildlife Refuge and
additional public lands near bases in Las Vegas and Reno.
Utah: Grand Staircase Escalante & Bears Ears National Monuments
One year ago, restoration of public’s right to collect rocks, minerals and common non-vertebrate fossils
took effect within a new special area, the Kanab-Escalante Planning Area (the land removed from the
GSENM), with new management plans for the GSENM and KEPA and revised GSNEM boundaries. The
BLM did not act hastily. After President’s Executive Order in 2018, no immediate change was made to
the monuments' boundaries and management. Public meeting were held and comments solicited. The
BLM drafted contrasting management proposals and once again solicited public comments (some rock
clubs, from across the country, signed a joint comment letter). Only after analyzing the comments from
all interested parties did the BLM decide on a new management plan, and implemented it in Feb 2020.
Our right to collect rocks and common fossils in this area (the KEPA) is again threatened. An Executive
Order issued Jan 20th by President Biden includes a section directing his new Interior Secretary, in
consultation with other Cabinet members, and tribal leaders, "to determine whether restoration of the
monument boundaries and conditions that existed as of January 20, 2017, would be appropriate." The
likely outcome is easy to foresee, since Biden and his new Interior Secretary have already stated their
desire to return to the old boundaries of both monuments. Not included in president Biden’s directive
is any consideration of the views of local residents, nor consultation with their elected state and local
representatives (all of Utah’s Senators and Representatives and the Governor issued a joint statement
opposing any rollback to old boundaries for the GSENM or Bears Ears). The many public comments
submitted to the BLM in 2019 and used in updating the management plans are, it seems, disregarded.
The Grand Staircase-Escalante NM was created by President Clinton in 1996. It has been controversial
ever since, and is opposed by the majority of local residents. A ban on collecting of rocks was enforced
immediately, even before any management plan was drafted. I have never been convinced of the need
for a complete ban over such a large area. After Trump’s executive order shrinking the GSNEM, the
media has exclusively published the dire predictions of those who objected, but not other viewpoints.
However, one year now after the new rules took effect, I have yet to see any news reports of actual
negative consequences to the public resources within the area removed from the GSENM (the KEPA).
The Bears Ears NM, created by executive order in the last days of Obama’s presidency, had no
management plan at the time of Trump’s executive order. Rock collecting is banned by the new 2020
management plan, so if that monument’s borders are enlarged, land will be removed from collecting.
DELVINGS February 2021 Page 4
IRON AND ITS ORES – Andrew Hoekstra
Iron is the most common element in the earth but most of it is found in the earth’s core. Iron is the
fourth most common element in the earth’s crust, and is the most common metal. But very little
natural metallic iron exists at the earth’s surface, and most of that which can be found is in meteorites.
Before people learned how to smelt iron from ore, they used meteorites: meteoritic iron was used in
Egypt as early as 3500 BC, and the indigenous people of Greenland used iron from the Cape York
Meteorite, one of the largest iron meteorites known. The Hittites seem to be the first people to
understand and practice large scale smelting of iron from ore, sometime after 1500 BC.
Only in the most massive “supergiant” stars is iron produced (by atomic fusion of silicon). All the iron
on the earth, and all the elements “heavier” than iron, including the iron inside of each of our bodies,
are believed to have originated inside supergiant stars, especially those that exploded as supernova.
GOETHITE (FeO[OH], iron hydroxide) – goethite is the most stable and common iron mineral and an
important ore. Rust is mostly goethite. Many other iron minerals alter to goethite over time, and
goethite often forms pseudomorphs. Goethite is rarely found as crystals (other than pseudomorphs). It
has a yellow streak and weathers (oxidizes) to a yellow color. Ochre is a name given to colorful earthy
goethite used as pigment. Goethite is exceedingly common, occurring as brown or gray botryoidal
crusts or earthy masses. LIMONITE is not a mineral but a blend of goethite and other iron oxides and
hydroxides. Limonite forms the gossan (iron hat/cap) at the surface over sulfide and gold-quartz veins,
and limonite is the “bog ore” of swamps. Limonite lacks the internal fibrous structure of goethite.
HEMATITE (Fe2O3, iron oxide) – the most important ore of iron, hematite is abundant and
widespread. It occurs as crystals but is more common in botryoidal or massive form. Hematite can be
red, brown, black or metallic grey and is distinguished by its red streak. Powdered red hematite is
known as Red Ochre. Massive deposits of hematite originated more than 2 billion years ago in the sea
when oxygen - produced by microbes (then the only life) - became sufficient to bond with and
precipitate the dissolved iron in seawater. The iron-rich sediments that formed are banded iron deposits
found around the world (once iron was precipitated from the sea, the ever increasing oxygen saturated
the ocean and accumulated in the earth’s atmosphere, making evolution of multi-cellular life possible).
An unusual iridescent ‘rainbow hematite” is found at only one locality, in Minas Gerais, Brazil.
MAGNETITE (Fe3O4, iron oxide) – differing in molecular structure and crystal form from hematite,
magnetite is more strongly attracted by a magnet than any other mineral. Some magnetite, known as
lodestone, is itself magnetic and attracts iron (if the net charge of unpaired thus unstable atoms is
aligned within the crystal structure). People have used lodestones for centuries, but today’s magnets are
artificial (ferrites). Particles of magnetite in rocks are useful for studying paleomagnetism, which can
reveal the age and movements of rocks and continents. Magnetite is useful today primarily as an ore of
iron. It has a black streak, and its opaque black crystals are octahedral or dodecahedral. Particles of
magnetite cause the iridescence of “rainbow obsidian.”
PYRITE (FeS2, iron sulfide) – this “fool’s gold” may be the most familiar iron mineral, and it is the most
abundant sulfide mineral. Its bright yellow color and metallic sheen, its distinctive cubic, octahedral,
and pryritohedral crystals, and their availability, make pyrite popular with all mineral collectors. Pyrite
is economically important as a source for sulfuric acid, and of course its iron content is used too. The
spectacular pyrite “sun” or “dollar” specimens seen for sale come from Illinois, and they are NOT fossils.
Fossils replaced with pyrite (or marcasite) are fairly common, including many from Ohio and Indiana.
DELVINGS February 2021 Page 5
MARCASITE (FeS2, iron sulfide) – marcasite is a polymorph of pyrite, with the same chemical
composition but a different molecular arrangement and crystal habit. It is more fragile and unstable
than pyrite (oxidizing to melanterite unless given a protective coating). The Victorian faceted gems
called marcasite are actually pyrite. Marcasite (from the Arabic markaschatsa, or “fire stone”) and
pyrite were used as fire-starters, sparking when struck against quartz. Marcasite is less common than
pyrite but has the same industrial uses, primarily as a source for sulfuric acid. Another iron sulfide,
PYRRHOTITE, is somewhat magnetic, usually massive, usually tarnished, and often found with pyrite.
SIDERITE (FeCO3, iron carbonate) – forming light brown crystals that can be transparent or
translucent, siderite does not necessarily look much like an iron or metallic mineral. But it is 48% iron
and can be used as an ore. Siderite is isomorphic with calcite, but is heavier, darker and does not
effervesce in hydrochloric acid. Most siderite crystals are saddle-shaped “warped” rhombohedra.
There are many more iron-containing minerals. ARSENOPYRITE, BORNITE, CHROMITE,
PENTLANDITE, STANNITE, BRAVOITE, and WURTZITE, are ore minerals where iron is present
together with other metals. Many common silicate minerals contain iron. The abundant minerals
discussed above have in common that they are relatively insoluble. Soluble iron compounds, chlorides
and sulfates important to industry and in biology, are uncommon as minerals in nature, being unstable.
Top Left : Pyrite “Sun” from Il l inois
Top Right : Ir idescent Goethite from Spain
Bottom Right : Siderite on Galena & Quartz
Photos from Wikimedia Courtesy of Robert M. Lavinsky / Mindat
Delvers Gem & Mineral Society, Inc. - mailing address: 3833 San Anseline, Long Beach, CA 90808
DELVINGS
16643 Chicago Ave.
Bellflower, CA 90706
FIRST CLASS MAIL
Website: http://delversgemclub.wordpress.com/
And we also can be found at Facebook
Editor: Andrew Hoekstra. Email: [email protected]
Regular Meeting of the Delvers Gem and Mineral Society February 12th, 2021, at 7 PM
at the Holy Redeemer Church, 14515 Blaine Ave., Bellflower, CA
February meeting canceled! Visitors Always Welcome
Board Meeting (all members invited) at 6:15 PM
