Well, it is, but it might not be ground precisely enough to sharply focus the die image like the larger lenses.
Sorry to take this slightly off topic, but can you expand a bit on this? The KD aspheric lens (for my D cell Mag) that I mentioned is obviously aspherical - the aspheric I got from the shoppe (marked "mineral glass crystal MCT 227 1.0 mm"), for my MiniMag is only very slightly convex, maybe just, er, 1 mm compared to the massive dome of the KD/Ledean. Is your MM aspheric lens more obviously domed/bulbous? I'm thinking I ordered the wrong bit of kit
EDIT: just tried my cut-down MiniMag LED running a 14500 with all four of my Shoppe aspherical balls - not the lens - and I can see fissures and artefacts in each of them. Obviously at the price they are not sold as high-end optics, but wanted to mention that they are not perfect for those looking for the dream beam. It is, however, still possible to project a nicely square die