It's called a Sovereign's Orb which you can find out more about in the Crown Jewels of the United Kingdom wikipedia page.

They belong to the 'Crown' or the institution of the monarchy/state.

The Crown is represented by the Reigning Monarch, and is above the monarch in status (the crown is passed on from one monarch to the next). Don't think The Crown is some from of company or organisation. And don't think the Monarch owns the Crown. The Crown owns everything.

No.

Burj Dubai is in the United Arab Emirates (Asia)

French Crown Jewels are in France (Europe)

In the Tower of London, as part of the UK Crown Jewels

The Kohinoor diamond is a part Royal Collection housed in Queen's Gallery London. It is priceless.

The Koh-i-noor diamond is kept at the Tower of London Jewel House, set into a crown.

According to Wikipedia: "The Koh-i Nur is believed to have originated in the state of Andhra Pradesh in India."

Today, the diamond is mounted in Queer Alexandra's diamond crown and is considered part of the Crown Jewels of the United Kingdom. The Crown Jewels are kept in London, England.

aston wright built the crown jewels