Hi steve, there is something wrong with those ones - if you zoom in really close to their tip you can see that it's kind of messy there:





That thing that looks like a tiny squished flat edge actually appears to be a slivery thin tiny additional surface, and a degenerate face like that will interfere with calculation of the outward facing surface normals. So probably that little tiny face will need to be removed and the points of the large one squished down to a single point to make that into a proper solid without any degenerate things in it.

- Michael