Hi Diwa,
I have encountered asset block till now only for tax computation for India.
In India, depreciation on assets for the purpose of computation of net income as per the Income Tax (IT) Act 1961 is calculated over a block of assets instead of individual assets as allowed under the Companies Act 1956.
In order to peform this SAP has provided us with asset block feature (Assign Asset to Asset Block (J_1I_UPDBLKTOAST) - Depreciation - SAP Library). However, in case you want to calculate depreciation at individual asset level then you will need depreciation key. Also, Depreciation key facilitates us with period control method (apart from allowing us to define the depreciation calcuation methods) which I am not sure how to do with block key.
Is block key country specific concept? Because I have heard of Asset Block but not Block Key. Let me know in case you have any more input. It will be interesting to learn more about it.
Regards
Pankaj Pareek