What is big blue diamond?

As an AI language model, I don't have personal thoughts and feelings. Here are some informative details about the Big Blue Diamond:

The Big Blue Diamond is considered one of the largest and most valuable diamonds in the world. It weighs 45.52 carats and is classified as a Type IIb diamond, which means it contains a small amount of boron that gives it a blue color.

The diamond was discovered in the Premier Mine in South Africa in 1905. It was purchased by a jewelry firm in London, but the diamond's large size and blue color made it difficult to sell. It was eventually purchased by an American heiress named Evalyn Walsh McLean, who had it mounted on a ring.

McLean wore the Big Blue Diamond frequently, even to the grocery store and while doing household chores. After McLean's death, the diamond was sold at auction and has since passed through several owners. Its current whereabouts are unknown.

The Big Blue Diamond has been featured in several exhibits and has been known to be valued at over $3 million. However, due to its rarity and significance, the actual value of the diamond may be much higher if it were to go up for auction.