Inventory of materials and inventory stock

Is it possible to separate stocks of finished goods inventories of materials for production?

Yes. Both are created as inventory items. Then, production orders are used to convert component or raw material items into those that are finished goods.

Yes, by the use of Custom Control Accounts you can separately account for both.

Rename the existing “Inventory on Hand” account to “Finished Goods” under Settings - Chart of Accounts.
Create a new BS - Asset account called “Production Materials”, tick the Custom Control Account box and select Made up of “Inventories Items”

Then under Inventory Items leave the Finished Goods as they are but for the Production Materials - click Edit and under the Control account field select Production Materials