Answer: Thank you for your inquiries. The term "private" relating to gold coins refers to coins struck by private entities rather than government mints. Territorial is different and refers to coins that were struck in territories, not states. For example, California was a territory prior to 1850, and Colorado was also a territory when Clark, Gruber & Co. coins were minted.
The Alaskan discoveries in the Yukon took place in a large way in 1896, increasing to great interest in 1897 and 1898. I am not aware of any coins that were privately struck in connection with this. Regarding the Comstock Lode, this was developed in the late 1850s, continuing through the 1860s, and I am not aware of any privately issued coins in that connection.