o3de-atom-sampleviewer/Materials/BasePBR.material

{
    "materialType": "Materials/Types/BasePBR.materialtype",
    "materialTypeVersion": 5,
    "propertyValues": {
        "baseColor.textureMap": "Textures/Default/default_basecolor.tif",
        "normal.textureMap": "Textures/Default/default_normal.tif",
        "roughness.textureMap": "Textures/Default/default_roughness.tif"
    }
}