Capital Gains Sec 47(viic) and Sec 48 proviso 4

If you hold the bonds until maturity and get the invested money back on redemption of bonds then capital gain arising therefrom will be not taxable(or simply say exempt)

however if you sell it before redemption then capital gain will be taxable and you will also get indexation benefit on such bond.
usually bonds do not have indexation benefit but this gold bond has.

this is provided in 47(viic) and proviso to 48

Thankyou

Welcome ishan