Some even say quince was the apple which lured Eve. Due to its colour, fragrance and many seeds the fruit was dedicated by the Greeks to Aphrodite and by the Romans to Venus, the godesses of love, and a symbol for beauty, love, fertility and a happy marriage. The eating of a Quince pear at weddings is said to be preparative of sweet and delightful days between the married persons. The high concentration of mucilage in the seeds made them very popular as an aphrodisiac. Quince jelly has also a good reputation as an amorous adjuvant.
Quince is very rich in pectine.
Thus, the addition of small quantity of quince will rapidly solidify any quivering mass of jelly. The right map shows a zoomed part of the left map. Images on this document are taken from the pages they point to.