An April 1936 Witnessed Fall: Yurtuk, UkraineA Double Hammer Stone!Borne from Impact on an Asteroid.Hammered a House here on Earth. |
| To behold a howardite is to gaze upon the physical manifestation of the past and present dynamic processes of our solar system.Although howardites command some of the highest prices of the HEDs, essentially they are just asteroid dirt classified as a proportional mix of two or more aristocratic meteorites. |
What would you get if you tossed a eucrite and a diogenite in a blender?
According to meteorite dealer Blaine Reed, you would get a howardite.
Howardites are samples of the soil on an asteroid made from surface eucrites mixed with subsurface diogenites as well as a breccia of the impactor that brought the former two together.
Often the basaltic asteroid was hit by a chondrite so essentially a howardite is the resultant polymict breccia of the most popular achondrites and chondrites pulverized and recemented into a rare meteorite class named Edward Charles Howard (1774 -1816) a British chemist described as “the first chemical engineer of any distinction.
Howard was the first to notice the presence of a nickel-iron alloy across many different meteorites. Thusly meteorites are more chemically similar to each other than they are to the earth rocks.
| The common published description of the earthly arrival of Yurtuk is the following: In Mikhailov district, Lubimov, Ukraine, at about 1:00 in the morning on April 2, 1936, one stone of 509g fell through the roof of a house.Several more pieces were picked up outside the house including one of 51.5g. The total known weight of Yurtuk is 1.472kg. Although the total known weight is a paltry 1472 grams, two things stand out. First, the TKW is actually fairly large as far as howardites go, and second, the entire fall contains an unknown number of specimens. |
| Where do howardites come from? Well, they are basically the soil of an asteroid created through an impact mixing process described above.Essentially, the upper left of the diagram turns into the lower right. It’s actually a little more complex and fascinating than that so for a richer explanation, please consult the howardite entry in O. Richard Norton’s wonderful book Rocks from Space. [diagram reference: Labotka, T. C. & Papike, J. J. Howardites: Samples of the regolith of the parent body. Lunar and Planetary Science Conference, 11th, Houston, TX, March 17-21, 1980, Proceedings. Volume 2, 1980] |
| Except for the mid 20th century fall date, Yurtuk is a rare class of rare classes, a hammer stone of very small total known weight and low distribution. But Yurtuk, and all howardites for that matter, are actually “Double Hammers” because they are the offspring of a cosmic hammering before maturing to the point of continuing the circle of violence here on earth. The beauty of the howardite is within the anger from which it was created.One of the truly inspiring aspects of howardites is found within its matrix. The gorgeous intricacies of the howardite’s interior matches the excitement of any good junkyard. Rich with bits and pieces of past lives, the howardite is a reservoir of geologic jewels some more obvious than others. Note the green gem in the center of this picture. Looks to me like the hubcap off an old diogenite. |
| The fusion crust on Yurtuk, like any good calcium-rich achondrite, is a glossy jet black film providing about the most contrast possible between the interior and exterior of a meteorite: liquid tar on snow.For many, the Joy of Fusion Crust is found on the lesser weathered hot desert finds, but lest we forget what untouched crust looks like. Impossible to mistake. Hard to explain. To misquote somebody, “Talking about fresh fusion crust is like dancing about architecture.” Trust me. You’ll know it when you see it. But you might not believe it’s real. |
| Mouseover the above picture to see a color-inverted version. Swiping your mouse on an off the image allows your eyes to more quickly find interesting features that either image in isolation would not highlight.Yurtuk, like most howardites provides a potpourri of meteorites all embedded within one. The cut face above exhibits classic howardite texture which actually means it is a diverse conglomerate of eucrite, diogenite and chondrite fragments. I like to believe that the large dark likely condritic mass just right of center is actually a piece of the Ensisheim parent body. A stretch you think? Possibly, but consider that you just contemplated this concept for the first time in your life. How often does that happen in this column? |
For me, Yurtuk was one those highly collectable meteorites that had such a degree of availability saturation that I didn’t take it as seriously as I should have. Then one day, I literally woke up one morning and thought to myself, “Why have I not bought the great piece of Yurtuk listed on a particular dealer’s website?”
Later that day, after making an offer followed by a humble explanation to the dealer as to who was emailing him (silly me. I thought everyone would recognize all my different email addresses.) we shook electronic hand on the deal. A week later, I was staring at a gorgeous specimen of Yurtuk that was actually fairly large as far as private collections go.
Shortly after the Yurtuk took up residence in my collection, it occurred to me that there was another specimen or two that although were at the top of my want-list, had eluded me for years. And this particular dealer might just be able to help me out.
Until next time….
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