Very early small gathering basket with swabbed coal tar dye splint near the bottom of the basket. I have seen this smaller size of gathering basket called a "berry basket" perhaps because it's small size is suitable for berries rather than corn, potatoes or fiddleheads. This has a coal tar dyed splint near the bottom of the basket.
Similar baskets can be found in Fannie Hardy Eckstorm's small book "Handicarfts of the Modern Maine Indian" published in 1930. For illustrations she used baskets from the Abbe Museum (Mount Desert Island, Maine). In her book those similar were dated to about 1860. I have seen these baskets, still in the Abbe's collection and still dated about 1860.
This is 10.5" long, 5.5" across and 2.75" high to the basket rim, 7.75 to the basket handle top. Woven of brown ash splints with a thick carved bentwood rim and a carved bentwood handle that is notched to go around/over the rim this basket has very thin splints with 2 wider splints near the basket bottom, the thin weaver splints are 1/16", the widest at basket center is 1/2" and the dyed wider one near the bottom is 1/4".
It is in near perfect condition, there is 1 missing round of the splint wrapping the carved bentwood rim to the basket. And there are a few small areas of slight water staining.
Coal tar dye was used prior to the introduction of aniline dyes, which occurred in the early 1860's. Since aniline dyes are/were so much simpler to use and cheaper in dollars and time - very shortly after their introduction to East Coast Indian basketmakers, the older dyes, Indigo, coal tar, chromium yellow, vermillion red etc were discontinued. By 1880 aniline dye was virtually the only type of dye the basketmaker's used.
The use of very thin fine splints (1/16") on a basket ... and adding a few wider splints is a style generally used prior to 1870 and rarely after 1880. The notched bentwood handle as well as the thick bentwood rim on such a small basket - all indicators this piece is quite early - pre-1870... and from others I have seen, I would date this 1850-70