Sandstone is loose grains pressed into rock, so dream books read it as scattered efforts bound into something solid. Its warm colours and soft erosion link it to gentle, gradual change.
Where in your waking life have you met something like this lately?
My Cosmic Code has a private dream journal. Write a dream down and the app picks out the symbols in it, shows what dream books say about them and, over time, which words recur across your entries. The journal is stored on your device only.