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AMBER = fossil tree resin that is stable (so does not decay), hardened, buried in oxygen-free sediment for millions of years. Most originates from pine or coniferous trees
COPAL = semi-fossilized tree resin or sub-fossil resin. If copal stays buried and doesn’t decay for millions of years it becomes amber
Hardness - Amber = 2 to 2.5 on Mohs scale - Can be scratched with a knife Copal = 1.5 on Mohs scale - can be scratched with fingernail
Age - Amber -Most is 30 to 90 million years old Oldest found is 320 million years old Oldest with inclusions 230 million years old Copal- 50 to 1.6 million years old
Colors - Amber - 300 colors including blue, green, red, yellow, orange, brown UV light - amber will look blue
Copal - lighter citrine color UV light - copal does not change color
Location - Amber -Largest deposits are in the Baltic region. Followed by Dominican Republic, Sumatra. Found in every continent but Antarctica. Found in Arkansas and New Jersey Copal- East Africa and South America at tropical latitudes
Inclusions - Because it originates as tree resin (from tree healing itself), amber sometimes contains animal or plant material. Amber has preserved long-extinct insects for millions of years. More than 1000 extinct species of insects have been identified as a result of amber. Half of inclusions in amber are flies beetles, moths, spiders, gnats, bees, a possible feather from a theropod dinosaur. Baltic amber has only 1 inclusion per 1000 pieces found. Dominican amber has more inclusions.
Copal- Many inclusions but not extinct species Classification of Amber -Organic gem or gem material like coral or pearl It is not a true gemstone. Fun Facts: Uses: Amber - adornment, medicinal. Copal - varnish Largest amber = Sumatran blue amber 111.11 lbs, 50.4 kg 55x50x42 cm Mike’s 61.8 lbs, 27.8 kg 50x35x22 cm Electricity named for amber - when amber is rubbed with cloth (wool) it was discovered to produce sparks and attract small particles and feathers, husks and wood splinters. This force was given the name “electricity” after the greek word elektron, which means amber. We know this as static electricity.
Amber vs Copal vs Fake. Scrape with a knife- fake amber flakes real amber is powdery Fingernail - can not scratch real amber-can scratch copal and fake amber In salt water- amber floats - copal and fake amber sink Real amber warms up quickly in your hand. Hot needle test- real amber does not melt quickly and smells sooty, piney
Malachite is considered a rare gemstone in that the original deposits for the stones have been depleted leaving behind very few sources. The use of Malachite as gemstones and sculptural materials remains just as popular today as they were throughout history. It's quite common to cut the stone into beads or cabochons for jewelry. The fact that Malachite has such a rich color and one that doesn't fade with time or when exposed to light makes it particularly rare. The pictures shown are from the Demographic Republic of the Congo.
These unusual, eye-catching and unique specimens were mined in 1974 by Odwaldo Monteiro, and to the best of my knowledge, they have never been found again in Paraíba. They are well-known to Agate enthusiasts, but many mineral collectos are not aware that they exist. The most interesting aspect of these specimens is that they have strange geometric forms on the exterior which are completely filled with banded multicolor Agate. These forms are completely natural, and since they do not resemble any recognizable crystal form (most of them are quite different in shape), it is safe to assume that these are not casts or pseudomorphs. There are dozens of theories out there on how these specimens came into being, but nobody can agree, and it's essentially a guessing game for now. What's significant about this specimen is that it is not only colorful featuring bands of midnight blue, lavender, smoky and even golden Agate, but it's actually completely in tact.
One of Iowa‘s most productive and famous geode collecting regions can be found within a 35-mile radius of Keokuk, Iowa. Rock collectors commonly refer to geodes from this region as “Keokuk geodes.” In keeping with the world-renowned status of the Iowa geodes, the Iowa General Assembly declared it the official State Rock in 1967.
Most Iowa geodes are roughly spherical, often lumpy or cauliflower-like on the exterior, with diameters typically ranging from about two to six inches. However, specimens measuring up to 30 inches are known. The most prized geodes have hollow interiors, although many geodes are solid objects in which crystal growth has filled most or all of the interior volume. Geodes from the Keokuk area contain a variety of minerals, but quartz is dominant in most. Calcite is also a common and attractive mineral in many geodes, which occurs in a variety of crystal habits and colors. An additional 17 minerals have been identified in Keokuk geodes.
Our next meeting will be June 10th at Dahl Ford our meeting place 1310 East Kimberly Road Davenport, Iowa 52807. Meeting starts at 5PM and ends around 6PM. Our theme this month is Agates. Bring your favorite agate and bring some of your agates you found on our May Fieldtrip. Silent auction last 15 minutes of meeting. If you have something you want to sell bring it for the silent auction. Please message us if you have any questions. Call Mike Shumate (217-219-2315) or email firstname.lastname@example.org