Short summary - The Vanished Diamond, also translated as The Southern Star
Jules Gabriel Verne
An adventure-adventure novel that tells about the discovery of the unique diamond "Southern Star" and its further fate, which ended so unexpectedly.
The French engineer, specialist in mines, Cyprin Mere, goes to Africa to take part in the development of diamond mines. People from all over the world work here in difficult conditions. Black workers do most of the work under the scorching African sun.
At the beginning of his activity, Mere finds a diamond, for which he receives a small reward. He continues to search for noble stones. Mere hopes to find the "Stone of Wisdom". He plans to start their artificial production. At home, Mere was involved in the development of this theory. The engineer's invention - the reverberatory furnace - brings him good luck. In the metal fragments, he finds a huge diamond.
After a special cut that turned the diamond into a huge diamond, Mere shows it to the owner of the mine, Watkins. His daughter Alice names the diamond "South Star". African mine owners are not happy with the new competitor and threaten Mr. Mere. Suddenly, the South Star disappears. Mere's black friend, Matakit, who is hiding in the jungle, is suspected of the theft, which only adds to the suspicion.
After a chase that lasts for several weeks, Mere finally finds Matakit. He proves that he did not steal the stone. It seems that the story of the missing diamond will remain a mystery, but soon the case takes an unexpected turn. After the ostrich living at Watkins swallows the documents, Mere euthanizes the bird and, along with the papers, removes the "Southern Star" from its stomach. After lying in the stomach of an ostrich, the stone turned red and became even more valuable.