There are basicaly two major types of nylon team roping ropes.

Head ropes are usually 30 foot long and a softer " Lay" and easier to work with.

Heel ropes are generaly 35 foot in length and a stiffer "lay".

They should all have a strip of leather on the hondo,  protecting the "eye" of the rope.

There is such a thing as a right handed rope and a left handed rope, the twist form the factory is reverseved to the rope will coil and benenfit for either orintation style of swinging and delivering the loop.

Also popular are ropes for the "lil Cowpokes" used for dummy roping and practice.  These will have a small soft lay and 12 to 18 feet is normal. 

There are many variations and colors offered to the cowboys today and generally they are either 3 strand or four strand, and have differnt circumfrences, from 3/8th to 7/8th scants or fulls.  They may be a polyester blend, but as a rule they are mostly made of nylon.  The prices paid new for these ropes will vary from $15.00 to  $51.00.

I would say the weight of these nylon ropes would be 13 to 18 ounces.

There are also ropes made made of jute, sisal, polyester and braided rawhide.

The black you will find on most of these ropes comes from "dallying" on a saddle horn that is wrapped with layers of rubber tubbing and burns or melts into the nylon from the combined weight and friction of a 300 to 700 hundred pound steer or cow and a 1,000 pound horse as the roper catches the steer and dallies (wraps the rope around the saddle horn) and pulls or tows the steer in a different direction so they "heeler" can throw his nylon loop and catch what he hopes is two hind feet and he also dallies to his saddle horn.

The useful life of a nylon rope to a competition roper may be a few uses or several 100 uses, depending on the personal preference and level of competition of the roper.

I have only rambled on a few key points about ropes here and will edit and try to clean this up to be a more useful review.

I sell used ropes and the end result is often rope baskets or articles that are crafted by burning the ropes edges together with a soldering iron or hot glue as a general rule.  Many artists and craftpersons have elevated the burning into a fine art and thier works demand much money and are highly sought after.