Gold reserves (owned by governments) is one thing, gold ownership (private ownership) is kind of another. While officially India holds 500–600 metric tonnes of gold with anywhere between 6 and hr of it in Forex reserves, Indian people hold 20,000 tonnes of gold. In the US, for instance, it's been estimated (How Much Gold Does the common U.S. Household Own? - Antique Sage) that on the average 125.8 million American households each hold 64.7 grams of gold. This involves ~8140 metric tonnes.
In Germany, private gold ownership reportedly (The vast gold hoards held by Germany’s population - Ronan Manly) is within the range of 8918 tonnes. China apparently has 16000 tonnes of personal gold ownership, although I don’t have independent confirmation of this number.
Finally a touch Infographic: The Indian Gold Market by BullionStar
A bit of an aside to produce history “For much of the last 2000 years of recorded history, India has been the most important buyer of gold. Roman historian, Pliny, lamented some 1800 years ago, how India, the sink of precious metals, was draining Rome of gold – an appellation that resonates even today.”
A truism if there was one - every invader to India from Alexander to the 2 Mahmuds (of Ghazni and Ghori) to the British, their entire reason to be in India was to induce their hands on the fabled gold.
An example of historical gold holdings: Malik Kafur, a General of Allauddin Khilji, went on a conquest of South India within the early 1300s and is meant to possess brought back 96000 ‘mans’ of gold from that expedition alone. [History of India: Volume 3/Chapter 5, Medieval India from the Mohammedan Conquest to the Reign of Akbar the good, by Stanley Lane-Poole, M.A., Litt.D., M.R.I.A., Professor of Arabic at Trinity College, Dublin] There are more sources for this factoid, which actually traces back to contemporary Muslim historians, so it should be considered credible.
Various sources have put a person at 25 pounds, 28 pounds, 33 pounds and 55 pounds by Hobson-Jobson - A Glossary of Anglo-Indian Colloquial Words and Phrases. Considering a middling 30 pounds, this alone involves 1300 metric tons! 1300 Metric tons from one campaign! Take it with a grain of salt if you may.
Conclusion: Hope this helps put a special perspective on gold.