To better demonstrate what I meant above, I snapped some photos below. The stone itself does matter ofc. Each chalcedony is different, so some may not vary as much or even more. And that's part of the reason why I love chalcedony too, each one is unique!
For my pieces, some times they look lavender blue, some times they look grey. And the textures of the stone is most obvious when under low light or against darker backgrounds. This is also the times where it appears greyer to me. Chalcedony also reminds me of a Chanel lavendar color from season 21k. Technically it is lilac/lavender, but it could appear grey under certain lighting. But anyway, hope these pictures help give you a better idea of what I meant
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