Green’s Dictionary of Slang

(US) an epithet used to describe cheap or sham jewellery; also used fig. (see cit. 1886).

1853		Life in Boston & N.Y. (Boston, MA) 1 Oct. n.p.: He says he does not deal in ‘Attleboro’ jewelry.
1859		Matsell Vocabulum 9: attleborough, Not genuine; made to imitate. At the town of Attleborough jewelry is manufactured from the baser metals, or so alloyed as to deceive those who are not judges of the genuine article.
1859		‘Aguecheek’ [C. Fairbanks] Travels 329: Needy wantonness displaying its rouge and Attleborough jewelry all the more boldly because it feels that the ban of society is upon it!
1886		T. Parker Lessons from the World of Matter 100: Poor Attleborough jewels are all these, but the best that humanity could offer.
1889–90		Barrère & Leland Dict. of Sl., Jargon and Cant.
1890–1904		Farmer & Henley Sl. and Its Analogues.
1902		Kansas City Star (MO) 10 May 5/2: ‘Attleboro jewelry’ is the insult Mamie flings at Kitty over her engagement ring and Tommy has to swallow anent his new watch.