Korvai Borders, Bendhu and Petni Pallu
Traditionally, in Kanjivarams the body and border were woven separately. Korvai is the technique that joins the body with a contrast border in the weft. This leaves an uneven texture on the edge of the border where the body joins the border.
The tradition of weaving temple designs with the korvai border is also quite popular in the Kanchi design language. A hand woven temple is easy to identify as the serrated edges are on different levels unlike the precise ones seen in a powerloom.
Petni is the process of joining the pallu with the body on the warp. So you see the body warp (yellow) going into the pallu side (black) while the pallu warp goes into the body side leaving an almost 2 inch width of intermingled coloured fabric. The edges of which has the extra yarn of either side which is cut close to the fabric.
This requires a skilled weaver and is rarely being woven today.
A bendhu pallu appears similar to petni only to the extent where the extra yarn is cut at the edges of the joint on the reverse side of the saree. The weaver takes either both the body and pallu yarn (pink and sea green) on both ends or only the body/pallu yarn on both ends of the joint.
