My question has already been answered in parts at Difference between state of matter and phase

But for deep and real understanding I have to ask for the difference between phase and a heterogenous mixture :

Say we have a bowl made of glass. The bowl is filled with a few different solid rocks on the ground, water in the middle and some oil on top.

I try to analyse this situation for understanding:

• There is a phase of oil on the top
• There is a phase of water in the middle
• There is a phase of rocks on the ground
• Since the rocks on the ground are not equally the same they are a bunch of single phases that do not mix up to each other
• The rocks on the ground are also a heterogenous mixture
• The air above the water is a phase of gas
• The glass is a solid phase of silicon

Is that correct?