wedge shaped blocks
In my limited experience you need something to contain the heat, either fire brick or a metal ring. At our camp someone installed a fire pit like you've stated, just bricks dry stacked in a circle. It's been three years since that was done, and the bricks are literally crumbling. I don't know if there are higher quality bricks, but it seems to me they are not made for that purpose and break down easily. Just a thought since you said you wanted to build it well to last. I'm of the same mindset and don't want to see my projects fall apart the next year.
Peace.
In my limited experience you need something to contain the heat, either fire brick or a metal ring. At our camp someone installed a fire pit like you've stated, just bricks dry stacked in a circle. It's been three years since that was done, and the bricks are literally crumbling. I don't know if there are higher quality bricks, but it seems to me they are not made for that purpose and break down easily. Just a thought since you said you wanted to build it well to last. I'm of the same mindset and don't want to see my projects fall apart the next year.
Peace.