While discussing the case of the Mishna (100b) regarding poorly dyed wool, our Gemara asks whether we view the dye that has changed the color of the wool as an independent entity or as something that has become part-and-parcel of the wool. The Gemara explains that this question can be raised, for example, in a case where a person stole wool together with prepared dye, and then dyed the wool with it. If the thief chooses to repent and return what he stole, is it enough to give back the newly dyed wool (i.e. would that be considered returning both the wool and the dye), or do we see it simply as wool and he would have to pay for the stolen dye, as well.
The Gemara suggests that the answer to this question is obvious. Since the wool is now more valuable than it was before, it is clear that the wool contains the value of the dye, as well. The Gemara argues that this is not always the case, since there are times that dyed wool may be the same price as plain wool, or we may be dealing with a case where the product that was dyed was not wool, but kofa.
With regard to the case of kofa, one possibility suggested by Rashi is that the thief stole a monkey and dye, and colored the monkey, whose value would not change because it had been dyed. Rashi’s other approach is that the word kofa means a simple reed basket, whose value does not change if it is colored.
Other commentaries assume that the word kofa means a monkey and offer different interpretations of the Gemara’s response. According to an opinion in the Aruk, the Gemara is suggesting a case where a monkey owned by the thief colored the wool, in a manner that certainly did not increase its value. Tosafot interpret the case as one where the dyeing was done so poorly that the wool came out looking ugly – like a monkey.
Although the Gemara continues discussing this case, it does not reach a clear conclusion about the value of the dye that is subsumed within the wool.