This classified as a mold because it has it's original shape and surface of the fossil.

This is classified as its original remains because the ice kept it's tissue from decaying. 

Principle of Superposition & Principle of Cross Cutting Relationships

4 5 2 6 1 3

I think that 4 is the oldest because it's the layer closest to the bottom. 5 is the next closest to the bottom. 2 is an intrusion but the way 6 is layered on top of 2 tells me that 2 is third oldest, and 6 is fourth oldest. 1 is layered on top of 6 so it's the fifth oldest. 3 is an intrusion that goes all the way to the top, I know that intrusions are younger that the layers of rock they cut through and it cuts through each layer. Therefore, number 3 is the youngest