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Page established 10-10-2000, updated 10-13-2001
Comments: Scale Bar is 0.5 mm. About 50 times more conodonts were recovered from this soft amorphous vein than were found in the hard crystallized limestone surrounding it. This was the among the largest of about 250 elements recovered in this sample. Picture taken under oil immersion. Notice the "white matter" is coated by a tough layer that is almost transparent. The cusp appears to have been cracked late in development by lateral force, and then "healed over" with asymmetrical enamel layers that gradually compensated for the deviation. The enamel cracked at right angles to the lamina, but the white matter cracked in a longitudinal fashion. Notice the denticles on the left appear to have been "added on" with abnormal growth over the outside of the element, suggesting the animal may have compensated for the bent cusp. Side view X02 looks directly down on crack. Views 04 and 05 give a closer look at the crack. 06, 07 and 08 give high-magnification focus to the point where the small side of the crack penetrates completely through the enamel lamina. Regrettably, this facinating conodont was accidently crushed during study. The final view 09 shows the appearance of a recent fracture. Fracture lines followed a similar Z-shaped path through the lamina and white matter of the interior.
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