This is, I am 99% certain, a very rare Century color: Model no. 104, Yellow lava in Blue-Green liquid! Approximated by today's yellow/blue, but not matched - I have a catalog showing a photo of a 104, and this is it! Cheap, too, and with a nice box. I'm not kidding about this, this is not one of those laughable "Look, I'm selling something really rare!" auctions; in fact, this seller seems to see nothing at all unusual about it. Note it has the early-style coppery-brass base, and my guess is that this is one of the two-part bases with the top cone connected to an inner cylinder.
...someone grab it. I can't (broke) AND am up to my eyeballs in Centuries.
You may have seen mine, I have two two-part centuries. I have a mint green / clear (once a green - blue) with identical coppery base as shown above. And another that is yellow - deep green (with faded to silver base) also a two part century. Probably made within first 2 years of production.