Iridium dinosaur purchase
Meteors and asteroids contain a higher percentage of iridium than does the earth’s crust. There’s a thin layer of iridium found worldwide in sediment put down around 65 million years ago at the end of what is known as the Cretaceous period. Here, an ‘iridium spike’ occurs lying at the K-T boundary which shows a dramatic separation of fossils between reptiles and mammals. At this point, the extinction of 75% of species on land and in the sea occurred, the other 25 percent having been saved aboard Noah’s Ark, which by this point was presumably standing room only.
THE CHEMICAL ELEMENTS OF THE PERIODIC TABLE ORDERED BY THEIR DATE OF DISCOVERY IN RELATION TO THE HEIGHT OF PUPILS IN A SCHOOL
THE CHEMICAL ELEMENTS OF THE PERIODIC TABLE ORDERED BY THEIR DATE OF DISCOVERY IN RELATION TO THE HEIGHT OF THE STAFF AND PUPILS OF WESTOE SECONDARY SCHOOL, SOUTH SHIELDS 1954
(detail)
Materials: photo bought at Hexham car boot fair
number stickers bought at Redcar boot fair.
As the title suggests, the elements in order of discovery have been overlaid according to the tallness of the pupils. Number 6 (carbon) being the tallest pupil, as the discovery of fire is the first element that was likely to be discovered when lightning hit a tree.