Hard rocks like granite, marble, or slate are much denser, and therefore less likely to absorb water and explode when exposed to heat. Other rocks that are safe to use around and in your fire pit include fire-rate brick, lava glass, lava rocks, and poured concrete.
Should I put stone in the bottom of my fire pit?
Sandstone, river rocks, natural rocks, and gravel are not ideal fill for fire pits because they are more likely to crack or explode under high heat. No matter what type of fill you use, make sure the fill is dry when you light the fire. … Even wet lava rock can explode.
Do you have to dig a hole for a fire pit?
Fire-pit depth really depends on what you want and how into your project you’re going to get. For instance, if you just want a basic fire pit, dig about 6 to 8 inches down and call it good. You can go deeper if you want, but keep in mind that you don’t want the hole so deep you can’t enjoy watching the fire.
Can I use all purpose sand for fire pit?
Any type sand will work. … Don’t put sand in it! It just holds any moisture that may get in. Drill holes in the bottom and line bottom with chunks of fire brick or lava rock.