Firestone and Sandstone

Firestone noun - A sandstone that withstands intense heat; used to line fireplaces and furnaces and kilns.

Sandstone and firestone are semantically related. In some cases you can use "Sandstone" instead a noun "Firestone".

Sandstone noun - A sedimentary rock consisting of sand consolidated with some cement (clay or quartz etc.).

Firestone and sandstone are semantically related. Sometimes you can replace term "Firestone" with "Sandstone", this nouns are similar.