eaglercraft-1.8-workspace/desktopRuntime/resources/assets/minecraft/models/block/cube_top.json

{
    "parent": "block/cube",
    "textures": {
        "particle": "#side",
        "down": "#side",
        "up": "#top",
        "north": "#side",
        "east": "#side",
        "south": "#side",
        "west": "#side"
    }
}