Although unsigned, this miniature has been attributed to Thomas Edwards (1792->1866) who was active as a miniature painter in Boston from 1821-1866.
The portrait is similar to fig 13 in Strickler. With reference to two miniatures by Edwards, Strickler comments "Stylistically, these two miniatures share a delicate stipple technique, most noticeable in the background and flesh tones, and softly modelled and rounded facial features". Those comments seem to apply here.
The sitter is identified by a note inside as "John Webster Sept 10th born 1804 died Salem". There is also an accompanying tag which is hard to read, but appears to state "I think Buffington - portrait over fireplace - John Webster only son of - Fabers (?) may have first wife Buffington - first line?".
These comments have enabled the identification of the sitter as John Webster (10 Sep 1804->1880) of Salem (which is 4 miles from Danvers, MA and 20 miles from Boston.) who married Martha Buffington (1 Jul 1805->1870) of Danvers on Mar 7 1832 at Salem. Thus it was probably a marriage portrait painted around 1832, with the date and location fitting with Thomas Edwards as the artist.
John Webster was the son of Elijah C Webster (27 Feb 1774-28 Jun 1848) and Sarah Dole (Sally Dole) (?-16 Dec 1842)who were married at Danvers on 13 Nov 1800. He had a brother Albert R Webster and a sister Almira W Webster who both died young in 1811 and 1814.
John was born at Salem on 10 Sep 1804. Martha A Buffington was born at Danvers on 1 Jul 1805, the daughter of James Buffington and Abigail Osborne who were married on Apr 14 1801. (There are references to a Capt James Buffington from this area who sailed as far as Ceylon.) John Webster seems to have initially been a company agent in the 1850 census, then in the 1860 census he described himself as a clerk, although he and Martha did already have one live-in servant. However, in the 1870 and 1880 census records, he was still employed aged 65 and 75, and gave his occupation as Treasurer of New Hampshire (?) Manufacturing Company and in 1870 he had assets of $18,000.
If this is the correct reading of the company name, there does appear to have been a New Hampshire Manufacturing Company of Dover that sold sheeting, shirting, calicoes etc. see OSV - Document Viewer - Doc # 677 which may have been where he worked. 1246