Is depositing money in Al Baraka Islamic Bank investment certificates at a fixed rate considered usury?

It is not possible to rule on the investment certificates in the aforementioned bank without knowing its system and conditions. The decisive factor is the bank's adherence to Sharia guidelines, which are: that the bank invests the capital in permissible ways, that the profit ratio is shared between both parties and not guaranteed, that the capital is not guaranteed, and that the bank does not invest funds in prohibited transactions. If these guidelines are met, then investment is permissible, and this is known as Mudarabah.