I was dropping sand in lava in the nether and expecting it to hit the floor and have a pillar of sand. Instead I found that the sand was disappearing. I tested this with anvils and it disappeared as well. 

What I expected to happen was...:
I expected the sand to pile upwards

What actually happened was...:
the falling sand became a item entity and burned up in the lava mid fall

Steps to Reproduce:
1. have a soul sand floor and above it place atleast 20 blocks of lava
2. drop some sort of gravity affected block. (anvil, sand, gravel etc.)