You are too kind @d-pend. This month I have been researching ideas for the bonsai landscape scene I am going to make. Most of the rocks I'll be using look like basalt, similar to those in your photos. Anything that shows young and old trees growing up through the rocks or along hills is a helpful reference. I need to try to recreate nature, by making a believable scene. It is good for me to study how the rocks interlock and and angle through the earth to make an interesting landscape, and to see where the trees grow.

https://steemit.com/nature/@creativetruth/rock-hunt-treasure-trove-bonsai

https://steemit.com/bonsai/@creativetruth/developing-rock-landscape-ideas-for-seedlings-bonsai

In a couple weeks I'll be building with the materials I collected by adding clay-mud and small bonsai trees.