As leather matures, it does go darker, but if you look after them and follow proper care and clean instructions they will not easily change colour, unless leather cream is applied. We have two products you can use to take care of your vellies; leather cream and leather sealant. The leather sealant makes your shoes oil and water repellent. It's a great product to start with to take care of your vellies. We recommend using the leather cream only after your vellies are showing signs of dryness, as the cream darkens leather.