No two pieces of natural jade are quite the same — subtle differences in tone, translucency, and the occasional small fleck are simply part of genuine stone, not a flaw.
You may also notice your roller looking a touch richer or darker with regular use. That's not the jade changing colour — it's the stone absorbing natural oils from your skin over time, which fill tiny surface pores and make it more translucent. As light passes through a clearer stone, the green simply appears deeper and more vivid.
In Chinese tradition, this is considered a good sign. There's a well-loved saying — 人养玉,玉养人 ("people nourish jade, and jade nourishes people") — reflecting the bond that grows between a stone and the person who wears it. Science or symbolism, we like to think of it as your jade settling in and becoming truly yours.