Heat Proof silicone

[G_ReG23]

Hi all,
I have a brick pizza oven with a cast concrete arch at the front.
Due to different expansion rates, the concrete arch always comes loose from the bricks.
Is there a silicone/adhesive/mastic I could use to re attach the arch that can withstand the heat and allow it move but not come loose?

[UtahBeehiver]

Inswool or Kaowool moudable caulk are high temp caulks (2000F) are a couple options.