Details of a sister diamond to the famous Koh-i-Noor (Mountain of Light in Persian) have been found in documents from 1840 discovered by The Tribune.

Like its well-known sibling, the Daria-i-Noor (Ocean of Light) was quarried from Andhra Pradesh’s Golconda mines before it was acquired by a succession of royal rulers, including Maratha kings, Nawab Sirajul Mulk of Hyderabad and Nadir Shah of Persia.

And again, like the Koh-i-Noor, the Daria-i-Noor was later acquired by Maharaja Ranjit Singh and became part of his famous Toshakhana (treasury).

Stunning details of what the Toshakhana contained soon after it was “confiscated” by the East India Company include an item-by-item listing prepared over a period of three months by Dr John Login, later appointed the guardian of Ranjit Singh's son and heir Maharaja Dalip Singh.

Heading the Toshakhana list is the Koh-i-Noor -- the most famous diamond of its day and an object of obsessive fascination for the colonial authorities. Its current value is estimated at some £10.5 billion.

Before it was sent to the UK, this diamond was in the safekeeping of Login, who later handed it over to the then Governor-General Lord Dalhousie. He personally carried it with him to London as a spoil of war. In 1850, the young Maharaja Dalip Singh, who had been converted to Christianity, was induced to present the Koh-i-Noor as a “gift” to Queen Victoria.

Originally the size of an egg, the Koh-i-Noor was 186 carats (approximately 37 gm), but was reduced to 105 carats (21.6 gm) after it was re-cut on the instructions of the British royal family. It was originally mounted in a brooch, but is now set into the Crown of Queen Elizabeth and on display at the Tower of London.

In his description sent to the India Office, Login explains that the Koh-i-Noor is set as an armlet with additional decorations of 11 pearls, three smaller diamonds and 11 garnets with a weight 12.7 tolas. He does not estimate the Koh-i-Noor’s value, although the estimates at the time valued it at several million pounds, making it worth over £10 billion in today's prices.

By contrast, the Daria-i-Noor is valued by Login at Rs 63,000, the equivalent of £6,000 in 1840 and more than £100 million today. Like the Koh-i-Noor, the Daria-i-Noor also had 11 pearls with 11 supporting diamonds and 11 garnets known as ‘choonee’. Its weight was 10.8 tolas.

In his letter to the East India Company (also seen by The Tribune) explaining how he took three months to prepare a list if the valuables in the Toshakhana, Login says: "I have the honour herewith to submit a list (in detail and abstract) of jewels lately transferred from the treasury (Toshakhana) of the Lahore Durbar to the Hon'ble Company Treasury in the Motee Munder.

“It comprises all those which are considered state (khas) jewels, as well as such as have been kept for presentation, and the value of the whole, exclusive of the Koh-i-noor diamond is estimated at the sum of sixteen lakhs, forty one thousand and thirty-five rupees and eight annas (Rs 16,41,035-8),” Login writes.

“In addition, however, to the above I expect that jewels to the value of more than 50,000 rupees may yet be found among the miscellaneous articles in the Toshakhana, which are under inspection, but the manner in which some of the most valuable articles have been disposed of in the store rooms, without order or arrangement, renders it very difficult to form an accurate estimate of the subject," he concluded in his letter to the East India Company.

Some of the other precious items included two gold armlets -- each set with 32 pearls, 22 diamonds and 14 rubies -- two armlets of six emeralds each valued at Rs 10,000, a plume for a turban decorated with 51 pearls and 10 diamonds and valued at Rs 14,000, another plume of gold decorated with 144 pearls, 22 emeralds, 85 diamonds and 44 garnets valued at Rs 4,200.

Still more opulent and mysteriously under-priced was the plume decorated with 669 pearls, 15 emeralds, 66 diamonds and two rubies at only Rs 2,650 (£265). Based on the change in the retail price index, the plume would be worth some £18,000 today.

As for the Daria-i-Noor, it was also taken to London, but did not attract the interest of the British royals. Two years later, it was sent back to India where it was bought at an auction by one of the Nawabs of Dhaka. It is currently said to be preserved in the vault of a Bangladeshi bank.

Similar, yet so different

* The pale pink Daria-i-Noor (Ocean of Light) is one of the rarest among diamonds

* Like the Koh-i-Noor, it was quarried from the Golconda mines and acquired by a succession of rulers till Maharaja Ranjit Singh got it

* The Daria-i-Noor was also taken to London, but did not interest the British royals

* It was bought by one of the Nawabs of Dhaka and is currently said to be in the vault of a Bangladeshi bank