From the seller:
A glorious 1860’s three piece pink silk ball gown/dress that has been de-accessioned from the Metropolitan Museum of Art. The ensemble consists of an evening bodice, over skirt and long trained underskirt. The dress also comes with a belt that has a center back bow attachment. The fabric has a changeable quality depending on the light reflection. The bodice has round neckline and short puffed sleeve. The bodice is decorated with pink silk ruffles that are fringed along the edge. It is also trimmed with white tulle net lace. The bodice is lined with cotton and has a back button closure. The unlined overskirt is trimmed with ruffles and tulle lace remnants. The under skirt is plain and is lined at the hemline with a wide band of cotton and small remnants of the original buckram lining. The dress is in very good and sturdy condition. There is a 2 inch split near the wait on the over skirt but no other splits or holes. The bodice has no underarm discoloration. There is a 2 /12 inch watermark on the front of the bodice. Both the over skirt and underskirt need to have their wait bands re-attached. The underskirt has some scattered water spotting and soiling along the edge of the hemline. The tulle net lace is in fragile condition and most is missing on the over skirt. Bust 30 Waist 22 Front skirt length 42 Back length 62 Width at hemline 180.
Although the above fashion plate is probably a year later than the extant dress, you can see some of the similarities in the skirt and the fringe. My guess is 1867.