Specialist work that mends damaged rugs, including re-knotting or reweaving worn areas, patching, overcasting (rebinding the edge), stretching, fringe replacement and color restoration. Small, skilled repairs that are hard to see are generally acceptable on an older rug, and an unrepaired rug commands the highest price. Visible patches, seams or stitching, easiest to spot from the back, and replaced fringes (the fringe being the rug's own warp ends, not a trim) count as major repairs that shorten a rug's life and lower its value considerably. Very old rugs often carry some repair, so a supposedly antique rug with none may be a newer recreation, though that clue alone is not conclusive.
The woven-in side edge of a hand-knotted rug, made during weaving as the weft is wrapped several times around the outermost warp to form a rounded, corded band. Depending on the region, the wrapping may use wool of a contrasting color, use the warp itself, or be kept flat rather than round, so the edge is one clue experts use to place a rug's origin. The word overcasting names this same edge and also appears in lists of common rug repairs.