"was exceptional among" is correct and usable in written English.
It is used to describe someone or something that stands out from others in a group. For example: "John's performance in the competition was exceptional among all the other competitors."
Her Russian was — in her husband's estimation — "stupendous"; her memory for poetry was exceptional (among much else, she knew "Eugene Onegin" and virtually all of Nabokov's verse by heart); she was supremely sensitive to a well-turned sentence; she seemed to thrive on living a life outside her own.
In this, Engberg points out, Motherwell was exceptional among the first generation of Abstract Expressionists, who tended to be lone wolves.
Shaw's plays, like those of Oscar Wilde, contained incisive humour, which was exceptional among playwrights of the Victorian era; both authors are remembered for their comedy.
Formal preparation prior to IHE beyond self-study was exceptional among our analysed sample.
However, the relationship between BMI and stillbirth risk was exceptional among South Asian women with a disproportionately high stillbirth rate observed among obese women.
The United States is exceptional among the latter countries in making no provision at all except in aid to dependent children paid on a means-tested basis.
America is exceptional among rich countries in this respect.
Brendel is exceptional among musicians for the selflessness with which he plays.
These qualities were exceptional among the Yamato-e painters of the time.
A purely mythological painting in the Renaissance tradition, Hercules is exceptional among Dürer's works.
The musk deer (Moschus moschiferus) is exceptional among deer in retaining a diffuse placenta.
