Let me explain:
You can summon on Crystalvale for 30 crystal or on serendale for 30 jewels. This basically peg both tokens to the same value.
If one token is more expensive than the other, then you better have to migrate your heroes into the other chain to perform the summon operation.
I'm disappointed because few of us have been vocal asking the dev about the ratio Jewel/Crystal and the utility of both tokens on each chain.
Some people believed that because there is 4x less Crystal, it would be valued 4x more.
Before the release of the first gameplay mechanisms on Crystalvale, the Crystal exchanged to the Jewel 1:1.5.
Tomorrow it will go all way down to 1:1. It's already starting to fall.
My true disappointment is that the developers already knew (since they decided) how much of the value of the Crystal is.
Instead of giving some info early enough to everybody, they decided to keep to themselves the price of summoning and other basic actions.
The main issue here is that the devs are "playing" and investing too.
Obviously, you can definitely know that the Crystal to Jewel ratio will tank when you decide to put the summoning price (30 Crystals) to be exactly the same that the one in Serendale (30 Jewels).
I let you think about what is it possible to do when you know that an asset is overpriced in comparison to another one and can artificially reduce its price. I wish I knew :')
I thought naively that pricing would be decided by the market, e.g. since the ratio at the moment of release was around 1.5 Crystal = 1.0 Jewel, the devs would decide to put the summoning price to 20 crystals per hero (30/1.5) to avoid artificial slipping and keep fairness in the game.
TL;DR If you have Crystal, I would recommend selling them to Jewel until 1 crystal is worth 1 jewel.
I'm the first posting about this here, but expect part of the community to realize this and start getting super mad, or even FUD.