This miniature portrait is by Antonio Meucci, (Aka Anthony Meucci) (?-1852). It is signed on the right edge "Meucci".
Meucci was born in Italy, but emigrated to the United States in 1818, where he painted miniatures between 1818 and 1827, before leaving for Central and South America. He died in Peru in 1852.
He worked in various American cities including New York, Portland (Maine), Richmond, Baltimore, Charleston, Salem MA, and New Orleans.
His wife Nina Meucci was also a miniature painter and in 1824 they exhibited four miniatures at the American Academy of Fine Arts.
On the reverse, this miniature is inscribed "A. Leache Age 17 yrs 1825", so it is definitely from his American period.
However, to date, it has not been possible to identify the sitter more closely.
As with other European artists, Meucci's European training is evident in the use of gouache, rather than water color, and also in the plain opaque background.
There is another miniature in this collection by Meucci. It is of an unknown man and can be seen in more detail at American Miniature Portraits - 1: Meucci, Antonio - portrait of a man
Meucci often used pink tones in his backgrounds, as can be seen in both these examples. 1361
A descendant of Meucci who lives in Chile, has kindly provided a lot of background information about Meucci. It can be seen, together with many more examples of his work, at Guest Gallery: Chilean collector - Antonio Meucci portraits