- Dated: 19th century
- Medium: bronze
- Measurements: overall length 23 cm
The handle of the dagger is ornate with a skeleton around which a snake is coiled.
Source: Copyright © 2014 Expertissim
These gifs depict the moment a mineral forms. Researchers at the Pacific Northwest National Laboratory trained a powerful microscope on the birth of calcium carbonate crystals, a process called nucleation.
To see the unpredictable moment when the seed of a crystal starts rapidly growing, they mixed high concentrations of sodium bicarbonate and calcium chloride in water. They then focused a transmission electron microscope that produces images in real time on the solution.
"This is the first time we have directly visualized the formation process," said materials scientist James De Yoreo. "We observed many pathways happening simultaneously. And they happened randomly. We were never able to predict what was going to come up next."