You are correct. One of the reasons for that is that, presently, 3N-4N Si is not a standard product, but a made to order one.  So the price per $/kg is never for the raw product, but always for a transformed version of the material.  One must be very careful not to try to extrapolate too much from laboratory scale sale price in $/kg, as commercial-scale production and sale price will be base on market dynamics and realities.

We have done some market studies about the potential value that we could get for 3N-4N purity materials, and we are actually working with Apollon Solar to update these numbers.  Unfortunately, disclosure rules are such that we cannot share these numbers in public, but what I can say is that Pyro and HPQ would not have bothered to create HPQ NANO if these numbers were not very promising.

Regards

Bernard Tourillon