Read this article about a recent discovery in South Africa. Do you know the meaning of the orange words? When you have finished reading, match the words to their meanings.
A rare blue diamond has been found at a South African mine famous for being the location of some of the most valuable gems ever unearthed.
The 29.6-carat stone was recovered by Petra Diamonds at its Cullinan mine, about 40km (25 miles) north-east of Pretoria.
A company spokesman told the BBC: "This stone is one of the most exceptional stones recovered at Cullinan during Petra's operation of the mine.
"The stone is an outstanding vivid blue with extraordinary saturation, tone and clarity, and has the potential to yield a polished stone of great value and importance."
Other notable diamonds found in the mine include a 25.5 carat Cullinan blue dimond, found in 2013 and sold for $16.9 million, and a diamond found in 2008, known as the Star of Josephine, which was sold for $9.49 million.
Analyst Cailey Barker at brokers Numis thought the diamond could fetch between $15 million and $20 million at auction.
Petra Diamonds said the company would decide what to do with the diamond in the next week.
Now match the orange words to their defintions:
