Durability, color behavior and conservation: what a collector should know about oil paint.
Oil allows something no other medium resolves the same way: time. Slow drying, layers, glazes and corrections that leave a trace. That is also the reason for its conservation value.
Basic conservation
Indirect light, stable humidity between 45 and 55%, never above an active fireplace. Dust with a soft brush only; anything more, through a conservator.
What to ask before buying
Stretcher type, canvas preparation, whether the piece is varnished and with what. A serious artist answers without hesitation.