I will add some more of my findings, I`m not an expert,
but since I was a kid I gathered all sorts of rocks,
I could spend days looking for rocks, and stones
I literally brought at least one bag of stones everyday (my mum was terryfied!)
I will uploud some of them to see if you can recognize them,
the upper one is not a metal, it does not react to magnet,
oh, and I found all of this in scotland
Thanks for your help
Lumps of rock come in all shapes and sizes, colours and patterns, weights and other properties.
You haven't found anything particularly exciting to us, but in a way the main thing is that you found your specimens interesting enough to collect. That means you are observing, comparing and questioning. Observation and curiosity are essential components of science. Keep it up.
The second one looks like mud cracks. And those do occur as a sedimentary structure in rocks (not just in modern sediments). But appearances can be deceptive: the pattern could be concretionary in origin, like the left-hand one in the first photo. I am thinking of the type of concretion called septarian nodule. In such concretions, the host rock is separated into chunks by mineral veins. It can happen that those veins dissolve, leaving a pattern in the host rock like we see here.
I can't tell how flat or one-sided the specimen in photo 2 is. If it is flat and one-sided, I would favour mud cracks as an ID. Otherwise, septarian nodule.
The 3rd photo shows just lumps of rock, possibly sandstone.
The other photos seem to show a fine-grained grey limestone or siltstone, with some small fossil shell fragments seen as curved white lines. The large hole has several possible explanations, eg.:
- where a stone or fossil fell out
- where a fossil dissolved (as has been suggested)
- created by a boring marine mollusc
- man-made (perhaps when the rock was part of a larger piece)
Since there are no details left (lost due to erosion), we will never know for sure the origin of the cavity.