Is it totally safe to invest in RBI gold denominated bonds that come out frequently? What are the risks in the same?

This has been launched by the RBI about two years back and is becoming a popular mode of investments. The RBI Gold bonds are fully guaranteed by the government of India and backed by gold. At the end of the tenure, these gold bonds can be redeemed with the issuer. Typically, these gold bonds also get listed on the exchanges after 6 months of their issue. Regular tranches are issued by the RBI at intervals of 5-6 months. These gold bonds can be held in the form of gold certificates and also in your demat account. The biggest selling point of these gold bonds is that they also pay interest at the rate of 2.5%, which is an additional benefit apart from the gold price participation. It is also tax-efficient as there are no capital gains on redemption.