Mike, as you know quince grow better at the higher elevations and one of the traditional ways of using them was to turn them into preserves (glyko) as in the larger of the 2 jars in the photo. These, along with other produce, were brought down to the lower villages and sold at the annual festivals held in honour of the village saints. In our village that is St Luke who's name day is 18 Oct so that was when the various delicacies, etc, were bought and stockpiled. With the advent of improved roads and transport systems this is no longer the case, although I'm pleased to say that the Festival of St Luke is still held here and is one of the largest and best attended of them all.
The jar in the photo was obtained from a friend who lives in Kakopetria when we visited her a couple of weeks ago so we don't need to wait until 18 Oct!
The smaller jar contains a jam (jelly?) made from prickly pear fruit sweetened with Stevia.
On a personal note I have to admit to not being a great fan of sweet, sticky preserves though I understand the reasoning behind them, it being the best way to preserve things that had a short 'shelf life' before the introduction of refrigeration.