[shareaholic app="share_buttons" id="5618116"]

John Kashuba

John is a natural history enthusiast living in Oregon.

Axtell CV3

Axtell CV3

A 6.2 kg stone was found in 1943 by a man cultivating a cotton field three miles south of Axtell, Texas. The family kept it until 1993 when it was bought by Blaine Reed and distributed. Except for some coloration from terrestrial weathering, it appears very similar to Allende. Close study shows that they are […]

Read More →

Read More →

Dellen Tagamite Sweden

Dellen Tagamite Sweden

Dellen Crater is a roundish lake system in central Sweden near the east coast 180 miles north of Stockholm. It is about 11 miles across. The impact that formed it occurred 89.0 ± 2.7 million years ago. Some of the impact rock from the site is called tagamite. It is a term that was introduced […]

Read More →

Read More →

CK Chondrites

CK Chondrites

CK chondrites, Karoondites, contain objects that hint at the processes that produced the rocks we have in our collections. Here are a few.                        

Read More →

Read More →

NWA 5930 CV3

NWA 5930 CV3

NWA 5930 CV3 is interesting for the variety of chondrules, including non-textbook chondrules, it contains. Some are misshapen, several are rather large and relict grains are common. The textural contrasts are remarkable.

Read More →

Read More →

Coolidge C4 – ung

Coolidge C4 – ung

The namesake of the Coolidge grouplet of meteorites was found in 1937 and has been classified H4, CV4 and C3.8-ung. Studies distinguish Coolidge from CK chondrites (which contain type 4 examples) and from CV chondrites. Some chondrules are large and layered from repeated accretion and heating in the solar nebula.           […]

Read More →

Read More →

Angrites

Angrites

Angrites are achondrites consisting largely of augite.  Augite is a pyroxene containing calcium and, in this case, some titanium and aluminum.  Olivine and plagioclase make up the remaining bulk.  Angrites are the oldest known igneous rocks and probably came from a large parent body. Here are four photos each of three different angrites D’Orbigny   […]

Read More →

Read More →

Almahata Sitta

Almahata Sitta

It seems understatement to say that Almahata Sitta is polymict given that it contains at least twelve lithologies.  Since the  lithologic types are dominated by ureilites, though, it is classified as a polymict ureilite.  Much of the remainder is EL and EH chondrites of various petrographic grades, melts and breccias.  Also found are H and […]

Read More →

Read More →

NWA 6007 L3.5

NWA 6007 L3.5

NWA 6007 is terrestrially fresh but shocked. It has well defined chondrules as you would expect of an L3.5. Compression has caused an orientation of components within the stone. Dark inclusions are scattered throughout.                  

Read More →

Read More →

An Ungrouped Carbonaceous Chondrite

An Ungrouped Carbonaceous Chondrite

NWA 5958 C3.0-ung was 286 grams of fragments. We bought a fragment from Greg Hupé and had thin sections made from it. The Met Bull entry and two papers are here: http://www.lpi.usra.edu/meteor/metbull.php?code=50844 http://www.lpi.usra.edu/meetings/lpsc2011/pdf/2343.pdf http://www.lpi.usra.edu/meetings/lpsc2011/pdf/2325.pdf                      

Read More →

Read More →

Estherville Meteorite, a Mesosiderite

Estherville Meteorite, a Mesosiderite

Mesosiderite meteorites are stony irons with roughly 50-50 proportions of each. The iron is asteroidal core and the stone is the crust of a differentiated asteroid. Mantle material is rare. Several formation scenarios have been proposed and scientists continue to discuss the matter. Mesosiderites are classified by mineralogy and texture. Estherville is an A3/4. That […]

Read More →

Read More →

Metal-troilite Intergrowths

Metal-troilite Intergrowths

Sometimes melt rock in meteorites contains blebs of metal-troilite (FeS) intergrowths. Here are examples from two rocks. NWA 869 is the well known L3-6 regolith breccia. It took a pounding on the surface of its parent body and contains a variety of clasts including melt rock. All 95 grams of NWA 6579 is melt rock. […]

Read More →

Read More →

Moorabie L3.8-an

Moorabie L3.8-an

A few of us were talking meteorites when one friend mentioned Moorabie. When I couldn’t recall the stone I was admonished to refresh my memory as soon as possible. I make amends with this column. Even before checking my small collection I consulted David Weir’s Moorabie page to see what the score was. He lays […]

Read More →

Read More →

Vugs and Vacuoles in D’Orbigny Meteorite

Vugs and Vacuoles in D’Orbigny Meteorite

D’Orbigny The D’Orbigny angrite is famous for a lot of things. Among them are holes – vugs and vacuoles. The irregular vugs are usually filled with a tangle of well formed dark augite crystals. The vacuoles or vesicles are spherical. Most are empty. Some contain glass. These three dimensional features are hard to appreciate in […]

Read More →

Read More →

Seeing Processing in a CV3

Seeing Processing in a CV3

Not all CV3 carbonaceous chondrites are alike. More than most, NWA 6207 makes it easy for us to see that its components went through a succession of processes before they were delivered to us. Existing large mineral grains were incorporated into chondrules. Chondrules formed, solidified and then were included in subsequent chondrules. Mineral grains evolved, […]

Read More →

Read More →

Isheyevo

Isheyevo

Right now Isheyevo is being called a CH/CBb and might not even be a chondrite in the usual sense of the term. It is a complex mix of components from different sources. For example, there are two distinct populations of CAIs. There are two sets of chondrule textures corresponding to two blended lithologies. And the […]

Read More →

Read More →

Top