Rock and minerals are both considered to be natural substances and this is what they have in common.
In this excerpt, the statement that is the best interpretation of this excerpt is
<em>The narrator enjoys the peaceful surroundings of the mountains.</em>
This poem is not about preferences or adventures of any kind. The author wants to project to the reader the feelings that these elements produce on him. He uses the comparative with nature because of the conviction that it never changes.
When He says: "come, heart, where hill is heaped upon hill.." and mentions the mythical brotherhood of sun and moon and hollow and wood, and river and stream"
He is using these comparatives to represent the value of the happiness of giving love to another person without limit. It is the purest expression of love.