This specific 3D model, "Light Minimalist Diamond Ring 3D print model 30", is an asset made available by "Unknown author".
Can be downloaded at "Unknown platform" by following the link.
Usage of this 3d asset is subject to the "Unknown license" agreement.
STL (Stereolithography, filesize: 107 MB), JCAD (JewelCAD, filesize: 1.49 MB)