Here we have a picture I took a few days ago in the peak district. It's a spire of siliceous (high silicon dioxide content, in this case from quartz crystals) sand stone known and treasured amongst climbers as millstone grit for its great friction allowing delicate and exciting moves. It formed in the Carboniferous period when earth was sitting far closer to the equator as shown in the below diagram and in deltaic conditions. This means that it is from gradually laid down beds of sediment forming where a river runs out of energy to support what it is carrying and is what is responsible for horizontal (or tilted as seen in the image) weaknesses in the rock. The composition is mainly quartz as this minerals resistance means it lasts long enough to be eroded and deposited many times without breaking down. The quartz minerals in this rock may have come from previous outcrops and may yet form more outcrops for some sort of freaky future life forms to suction their way up!
The spire shown shows clear faulting which can be seen as horizontal breaks cutting through the slanting strata, this tells us that after the formation of this rock it has been tilted and then faulted several times before becoming the base of the famous route Valkryie!
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