Answers. Best Answer: The .925 does mean sterling silver and the FB may be a Hallmark. You did not state what is on the medallion so I don't know where it was made. On some silver items the FB stands for Franz Bibus a Czech silversmith.
The core of Darwin's theory is natural selection, a process that occurs over successive generations and is defined as the differential reproduction of genotypes. Natural selection requires heritable variation in a given trait, and differential survival and reproduction associated with possession of that trait.
Updated April 12, 2017. Directional selection is a type of natural selection that favors one extreme phenotype over the mean or another extreme. This phenomenon is usually seen in environments that have changed over time. Changes in weather, climate, or food availability lead to directional selection.