Widmanstatten lines

Widmanstatten lines
Etching slices of meteorites with nitric acid allow patterns known as Widmanstatten lines to be more visible. These lines and patterns are the result of the meteorite cooling in outer space over billions of years.
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Lines and patterns are the result of cooling in outer space over billions of years and etching slices with dilute nitric acid allow these patterns known as "Widmanstatten lines" to be more visible.

See also: Jewel, Jewelry, Etching, Gem, Stone