The 'Golden Axe' insignia was in use on the Arjun Main Battle Tank (MBT) even before the Narendra Modi-led NDA government came to power in 2014.
We identified the golden axe logo on the main Arjun battle tanks as belonging to the 12 Infantry division headquartered in Jaisalmer. Armoured Regiments like the 43 and the 75 Armoured regiments attached to this division also use the same insignia. While it is unclear when the 12 Infantry division adopted the golden axe insignia, we found the same insignia in a 2006 blog that says it belongs to the 12 Infantry Division. Various symbols are used on battle tanks to represent different army divisions. The 12 infantry division, also known as the ‘Battle Axe Division’, was officially formed in 1966.
Around 45 Arjun Mark 1 (MK 1) battle tanks were formally inducted into the 75 Armoured Regiment of the Indian Army in March 2011. Some of these battle tanks took part in the 2013 Republic day parade. The golden axe insignia can also be seen on India's Main Battle Tank Arjun MK 1 during the 2013 Republic day parade. The picture of an Arjun battle tank with the same golden axe insignia can be found in a Ministry of Defense photo cataloged in the Press Information Bureau's photo archives dated January 26, 2013.
Thus, it is evident that the golden axe insignia belongs to the 12 Infantry Division of the Indian Army and that the battle tanks from this division's 75 Armoured regiment also use the same insignia. The Narendra Modi government did not introduce the golden axe insignia, and it is definitely not a symbol of Sanatan, as some social media users claimed.