Neptune is primarily made of gas, not rock. It's classified as an ice giant, which means it's composed mostly of:

* Hydrogen and Helium: These are the lightest elements and make up the majority of Neptune's atmosphere.

* Ices: These include water, methane, and ammonia, which exist in solid form deep within the planet due to high pressure and temperature.

* Rocky Core: There's likely a small, solid core at the center of Neptune, but it's much smaller than the planet's overall size.

So, while Neptune does have a rocky core, it's dwarfed by the vast amounts of gas and ices that make up the majority of the planet.