The language description declares it is safe, but since you can dereference raw pointers, the language is not memory safe. Maybe it should be made clear that you are not claiming memory safety.
It is memory safe in the same way as Rust is. Rust allows you to de-reference a raw pointer, but only within an explicitly de-marked `unsafe` block. Cone will require a similar explicit mechanism. If you want the compiler to check your code for memory safety, don't use this mechanism. If you do use it, the responsibility for safety within rests on you, the programmer.
On it's own, pointer dereffing is not unsafe. Null pointers and out of bounds dereffing is what causes problems. Unless you're in an unsafe block I don't think Cone allows for arbitrary pointer shenanigans like C does.