The Portuguese Diamond is an unusual octagonal-cut

Cut (gems)

When a gemstone is desired to be used in jewelry, it is cut depending on the size and shape of the rough, as well as the desired piece of jewelry to be made. As a rule of thumb, a cut gemstone will reduce the mass by about 50 percent....

 diamond

Diamond

In mineralogy, diamond is an allotrope of carbon, where the carbon atoms are arranged in a variation of the face-centered cubic crystal structure called a diamond lattice. Diamond is less stable than graphite, but the conversion rate from diamond to graphite is negligible at ambient conditions...

 known for its flawlessness and clarity

Diamond clarity

Diamond clarity is a quality of diamonds relating to the existence and visual appearance of internal characteristics of a diamond called inclusions, and surface defects called blemishes. Clarity is one of the four Cs of diamond grading, the others being carat, color, and cut...

. It weighs 127.01 carats (25.4 g) and is regarded as one of the world's most magnificent diamond gems.

The Portuguese Diamond gives out a strong fluorescence

Fluorescence

Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation of a different wavelength. It is a form of luminescence. In most cases, emitted light has a longer wavelength, and therefore lower energy, than the absorbed radiation...

 under ultraviolet light. Under daylight or artificial light, the diamond gives out a soft fluorescence and a beautiful bluish haze.

The name "The Portuguese Diamond" was given by Harry Winston

Harry Winston

Harry Winston was an American jeweler. He donated the Hope Diamond to the Smithsonian Institution in 1958 after owning it for a decade, and traded the Portuguese Diamond to the Smithsonian in 1963.-History:...

, who previously owned the diamond.

History

According to one of the legends, the diamond was mined in Brazil in the eighteenth century and become part of the Portuguese crown jewels

Crown jewels

Crown jewels are jewels or artifacts of the reigning royal family of their respective country. They belong to monarchs and are passed to the next sovereign to symbolize the right to rule. They may include crowns, sceptres, orbs, swords, rings, and other objects...

. But there is no documentation that proves this story true. Documented reports of the diamond state that the diamond was most likely found at the Premier Mine

Premier Mine

The Premier Mine is an underground diamond mine owned by Petra Diamonds. It is situated in the town of Cullinan, 40 kilometres east of Pretoria, Gauteng Province, South Africa. Established in 1902, it was renamed the Cullinan Diamond Mine in November 2003 in celebration of its centenary...

 in Kimberly

Kimberley, Northern Cape

Kimberley is a city in South Africa, and the capital of the Northern Cape. It is located near the confluence of the Vaal and Orange Rivers. The town has considerable historical significance due its diamond mining past and siege during the Second Boer War...

, South Africa

South Africa

The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...

, in the early 20th century, after which it was bought and owned by many people.

The first documented record of the diamond finds its ownership with the Ziegfeld Follies

Ziegfeld Follies

The Ziegfeld Follies were a series of elaborate theatrical productions on Broadway in New York City from 1907 through 1931. They became a radio program in 1932 and 1936 as The Ziegfeld Follies of the Air....

 glamor woman named Peggy Hopkins Joyce

Peggy Hopkins Joyce

Peggy Hopkins Joyce was an American actress and celebrity, famed as much for her several marriages to wealthy men, colorful divorces, scandalous affairs, her diamonds and generally lavish lifestyle as for her work on stage or screen.-Brief Biography:Born Marguerite Upton in Berkley, Virginia, she...

 who bought the diamond from Black, Starr and Frost in February 1928. She traded her $350,000 pearl

Pearl

A pearl is a hard object produced within the soft tissue of a living shelled mollusk. Just like the shell of a mollusk, a pearl is made up of calcium carbonate in minute crystalline form, which has been deposited in concentric layers. The ideal pearl is perfectly round and smooth, but many other...

 necklace and additionally paid $23,000 in cash to purchase the diamond. She had the diamond mounted on a platinum choker

Choker

A choker is a close-fitting necklace, worn high on the neck. This type of jewellery can consist of one or more bands circling the neck. Chokers can be made of a variety of materials, including velvet, plastic, beads, metal, and leather. They are often adorned in a variety of ways, including with...

 that could be worn closely to the neck. In 1951, Harry Winston acquired the diamond from Joyce. The Portuguese Diamond was a part of his "Court of Jewels" until he sold it to an international industrialist in 1957. At present, the diamond belongs to the Smithsonian

Smithsonian Institution

The Smithsonian Institution is an educational and research institute and associated museum complex, administered and funded by the government of the United States and by funds from its endowment, contributions, and profits from its retail operations, concessions, licensing activities, and magazines...

's diamond collection after they acquired the diamond from Winston, in exchange for 2400 carats (480 g) of smaller diamonds.