Perfumers use only a few species of rose among the most scented: Rosa centifolia, also known as cabbage rose (in France) and Rosa damascena (in Turkey and Bulgaria). Rose is used in two extracts: the essential oil or the absolute, with the absolute being the deeper and sweeter variant.
Saffron smells strong, leathery, soft, earthy, hay-like, reminding slightly of rubber. The scent comes from the chemical compounds of picrocrocin and safranal. Saffron is often added to perfumes to support a leather chord.
Jasmine gives a richness and intensity to fragrances: a sweet floral note, but with a dead-sexy muskiness to it. If you smell different concentrated 'absolutes' (the oily liquids created through macerating the jasmine flowers), they have their own characters: some smell medicinal, some sweet, some musky, some green.