World’s Largest Star Rose Quartz – Michael Scott Collection

Origin of name

The Michael Scott Collection, arguably the most important private gem collection in the United States, with a few rivals in the world outside of the royal families, was started by Michael Scott, the first president of Apple Computer (1977-81), in 1987 and almost completed within a record-breaking period of 14 years. The collection includes spectacular examples of both rough crystals and faceted gemstones of all major as well as rare gemstone varieties, jewelry, and magnificent gem carvings, and also some antique jewelry from the mid-19th to early 20th centuries. This unique collection will remain an everlasting testimony to what an individual can achieve with total dedication and commitment to whatever field he might choose to apply himself. With a University Degree in Nuclear Physics, Scott went onto become the President of Apple Computer, which may not be quite relevant to his original field of study, and during a short period of five years, that represented the tenure of his service with the company, Apple Computer became one of the most successful companies in the United States. His interest in gemstones started in 1984-85 when he began reading on all aspects of gemstones and built up his knowledge on gemology. Having acquired sufficient knowledge of gemology he prepared a list of the pieces of gems he would like to have in his collection, and used  a small group of selected  and trusted brokers to go after what he wanted. This helped him to build his impressive collection within the shortest possible time.

World's Largest Rose Quartz

©Harold and Erica Van Pelt

One of the rare pieces in this extraordinary collection is a 5500-carat star rose quartz from Brazil, which is reputed to be the largest  star rose quartz in the world. This enormous gemstone qualifies to be placed under the list of world famous gemstones, but is as yet unnamed. This web page is dedicated to this unique and rare gemstone.

Characteristics of the gemstone

The world’s largest and finest star rose quartz

The gemstone that weighs an enormous 5500 carats is a spherical cabochon-cut, star rose quartz, with a rich pink color, good translucency and a perfect centrally placed six-rayed star, with distinct rays extending towards the girdle of the stone. The gemstone seems to contain the optimum quantity of rutile, that gives a perfect and distinct six-rayed star, without interfering with the translucency of the stone. The slight silky undertone visible in the stone is caused by rutile. The cut and polish of the stone is also perfect. Thus this extraordinary and unique gemstone combines the rare features of excellent color, good translucency and well defined star, making it the largest and finest star rose quartz in the world. In the Michael Scott collection the star rose quartz is mounted on a silver sculpture designed by the Seattle-based silversmith, John Marshall.

All features in this gemstone are so perfect that at a glance it may be mistaken for a star ruby with pinkish overtones such as the Sri Lankan star rubies, which are also famous for their well-defined stars. Its only the massive size of the gemstone that may give rise to doubts about it being classified as a star ruby, because as a rule, rubies of gem-quality cannot grow to such enormous sizes.

Classification of Quartz

Quartz which constitute about 12 % of the earth’s crust, is the most abundant mineral on earth, and occurs in igneous, metamorphic and sedimentary rocks. All varieties of quartz are crystalline forms of silicon dioxide. Quartz varieties are generally classified into two groups :- 1) macrocrystalline quartz  2) cryptocrystalline quartz, depending on the size of the individual crystals and whether these crystals can be seen with the naked eye.

Macrocrystalline quartz in which the individual grains or crystals are visible to the naked eye include the following varieties :-

Amethyst, Ametrine, Citrine, Milky Quartz, Prasiolite, Rock Crystal, Rose Quartz, and Smoky Quartz.

Cryptocrystalline quartz in which the individual grains are too small to be seen with the naked eye or sometimes even under the light microscope, are further subdivided into two types :- a) Fibrous known as Chalcedony and b) Granular known as Chert.

a) Chalcedony varieties :- Agate, Carnelian, Chrysoprase, Bloodstone, Onyx, Sardonyx, etc.

b) Chert varieties :- Flint, Jasper, Mozarkite

Some physical and optical properties of rose quartz

Quartz crystallizes in the Hexagonal-Rhombohedral crystal system, but the crystal habit of rose quartz is usually massive with occasional contact crystal faces. The specific gravity is 2.65. Quartz has a double refractive index of 1.544 and 1.553, and the birefringence which is the difference of the two is 0.009. The hardness of quartz is 7 on the Mohs scale, and the stones are generally opaque to translucent. Pleochroism in quartz can be weak to distinct.

The occurrence of rose quartz

Rose quartz normally occurs as massive formations inside the core of large pegmatites. Generally, the crystalline boundaries of individual crystals are distorted because of interference from other growing crystals. Thus large formations of rose quartz appear to be without crystals, and this apparent lack of crystals led mineralogists from around the world to dismiss the first discovered formations as fakes. A rare crystalline form of rose quartz have also been discovered in certain countries and are referred to as pink quartz.

The origin of Rose Quartz

Rose quartz is an igneous mineral originating deep inside the earth’s crust, by the solidification of granitic magma, which is molten rock. Plutons, which are huge masses of magma, being less dense than the surrounding rocks, are gradually driven up towards the surface of the earth. Plutons solidify several kilometers beneath the earth’s surface. As the pluton reaches the end of its migration, its temperature has sufficiently decreased and the magma crystallizes into solid minerals. The fluid magma near the edges of the pluton rich in volatile substances such as water, silica, oxygen and some other elements, may squirt and intrude into the surrounding rocks through fissures and fractures on the rock. While inside the rock the intrusions of magma (pegmatites) continues to cool and rose quartz gradually crystallizes. Depending on the quantity of fluid magma that has entered the rock enormous crystals of rose quartz can be produced. Other minerals such as feldspar and mica can also be formed at the same time. Most of the pegmatite intrusions containing rose quartz, found in different parts of the world, are about 1 to 2 billion years old, and are mainly of Precambrian origin. Thus rose quartz like corundum (rubies and sapphires) are archaic in origin.

Rose quartz, South Dakota’s official mineral stone

The main sources of rose quartz in the world today are the USA, Brazil, India, Germany, Sweden, Namibia, and Madagascar. In the USA the main sources of rose quartz are California, Maine and South Dakota. In the State of South Dakota, where rose quartz was first discovered near Custer, in the late 1880s, the rose quartz has been officially designated as the “State Mineral Stone” of the State of South Dakota.

What causes the color in Rose Quartz ?

Thus rose quartz is a macrocrystalline variety of the mineral quartz. The color of rose quartz varies from pale-pink to rose-red tones. The color is believed to be due to incorporation of trace quantities of atoms of transition elements such as titanium, iron or manganese in the crystal structure of quartz. However, recent X-ray diffraction studies have shown that the color may be caused by thin microscopic fibers occurring within the massive rose quartz structure, which may possibly be related to the mineral dumortierite. In the rare variety of rose quartz which occurs in crystalline form and known as pink quartz, the color is believed to be cause by aluminum and phosphorus impurities, but this color is photosensitive and can fade with time, on exposure to sunlight.

Uses of rose quartz

Only a fraction of the rose quartz mined is of gem quality. The mining of rose-quartz near Custer in South Dakota, has revealed that only one half of one percent for each ton of rose quartz mined, is  gem quality material. Thus, only a fraction of the rose quartz produced is used in lapidary work, and consequently for the production of jewelry. The bulk of the rose quartz produced is used as decorative pieces in landscaping and interior decoration, as tiles and mineral specimens for collectors. The color and hardness of rose quartz also make it a suitable material for carvings, such as figurines, ornate statues, obelisks, and others shapes like spheres and pyramids. There is evidence to show that the practice of carving rose quartz had been prevalent since ancient times, producing objects of worship and other religious symbols.

Asterism in rose quartz

Asterism is an optical phenomenon shown by some crystals when cut and polished en cabochon, producing a six-rayed or rarely a 12-rayed star by reflected or transmitted light, due to the presence of certain microscopic inclusions in the crystal, such as rutile fibers, that are arranged in a three-fold pattern inside the crystal, parallel to three crystal faces. Minerals that show this phenomenon include ruby and sapphires (corundum), quartz, beryl, chrysoberyl, crocidolite, garnet, diopside, spinel etc.

Rutile fibres were produced in minerals by a process known as exsolution, in which at high temperatures various impurities like rutile were incorporated into the lattice structure of the mineral during its formation, which was later forced out of the latttice when the mineral cooled. This is precisely the reason why asterism is not so common in most varieties of quartz, but seen quite often in rose quartz. Rose quartz developed inside pegmatite intrusions at high temperatures which also incorporated rutile, and when the crystals cooled down, the rutile was exsolved and formed inclusions. When the crystals are properly oriented and cut and polished with the dome-shaped face perpendicular to the c-axis, a distinct six-rayed star is produced when the crystal is exposed to a direct source of light. The star is best seen when light is viewed through the rose quartz, i.e. in transmitted light. This star effect known as “diasterism” is best seen when the stone is illuminated from behind. This is different from asterism in other gemstones such as ruby and sapphire, where stars are seen when light is shown on the gems, i.e. reflected light. This type of star effect is known as “epiasterism.” Another important observation that has been made is that smaller the rutile needles sharper is the star effect. If the needles are large enough to be visible to the naked eye as inclusions, the quartz becomes milky with a decreased translucency and lacks asterism.

History of the 5500-carat Rose Quartz

Minas Gerias Brazilian State

Minas Gerais the third largest state in Brazil

Photo Above Creative commons

Source of the Rose Quartz

The enormous 5500-carat Rose Quartz in the Michael Scott’s collection is believed to be of Brazilian origin. Today, Brazil is the main source of rose quartz in the world. Brazil is also the only source in the world of true well formed crystals of rose quartz. In Brazil rose quartz is found in Minas Gerais, the third largest state in the southeast region of Brazil. Minas Gerais in the Portuguese Language  means “general mines” or “large mines” a reference to the large mines of gold and precious stones discovered in the state in the 18th and 19th centuries.

Even today Minas Gerais produces a large variety of minerals, including large crystals of Beryl, Tourmaline and Quartz. Some of the minerals found in Minas Gerais are Diamond, Kunzite, Beryl (Aquamarine, Emerald and Morganite), Chrysoberyl, Quartz, Rose Quartz, Columbite, Albite, Tourmaline, Indicolite Tourmaline, Spessartite Garnet, Pyrrhotite, Titanite, Eosphorite, and Apatite. Thus, Minas Gerais is one of the most productive gem-mining regions on earth.

Cutting and polishing of the gemstone

The weight of the rough crystal from which the 5,500-carat rose quartz was derived is not known. The rough rose quartz was in all probability cut and polished in the United States. The spherical cabochon-cut of the stone is exceptional, and the dome-shaped face of the stone has been properly aligned so that it is perpendicular to the c-axis of the crystal. Thus the star has been exactly centered on the dome shaped face of the stone. The perfect cut and positioning of the star provides ample evidence in respect of the abilities of the expert cutter of this famous gemstone.

Another extra-ordinary difficulty faced in the cutting of star rose quartzes, is that the star is not visible in the rough stone, but is brought out only after cutting and polishing, with proper alignment of the dome-shaped face of the stone, perpendicular to the c-axis of the crystal. In a massive irregular crystal of rose quartz locating the c-axis alone will present enormous problems to the cutter. Thus the perfect cut of this stone is indeed a commendable achievement.

“Gems! The Art and Nature of Precious Stones” Exhibition

The 5500-carat star rose quartz was mounted on a a silver sculpture designed by the silversmith John Marshall of Seattle, in the year 1990. In February 2002, Bower’s Museum, California, hosted the exhibition titled “Gems! The Art and Nature of Precious Stones” in which Michael Scott’s magnificent collection of gems and minerals  were displayed. The exhibition which opened on February 16, 2002, was scheduled to close in August, but was extended for a much longer period of time, by popular demand. During this exhibition over 250 pieces of gemstones and minerals were put on display, highlighting the scientific as well as the artistic aspects of gemstones. The 5500-carat star rose quartz was one of the items on display. Some of the other prominent exhibits included a 65-carat cornflower blue sapphire guarded by a solid gold cobra, a 400.06-carat yellow sapphire mounted on a flower-shaped gold sculpture known as “Ceylon Sin Flower,” the “Demantoid Butterfly” set with 330 demantoid garnets and 472 diamonds, the “Queen of Kilimanjaro” tiara set with a 242-carat large Tanzanite (probably the world’s largest) 913 diamonds and 803 green tsavorite garnets, several large raw crystals, several cut and polished gemstones and colored diamonds, and sculptures made out of raw crystals, and also several pieces of antique jewelry. This exhibition was a tremendous success judging by the popular response.

Michael Scott’s Collection exhibited at the Shanghai Museum

Following the successful exhibition of the Michael Scott’s Collection at the Bower’s Museum in California, a request was made for the display of this magnificent collection at the Shanghai Museum in the year 2005. Scott agreed to this request and the collection was flown out to China in 2005, where it was exhibited at the Shanghai Museum. It is reported that over 850,000 visitors attended this exhibition, which was considered to be a great success. The 5500-carat star rose quartz was one of the exhibits at this exhibition.

“Gems! Colors of Light and Stone” Exhibition

The Michael Scott Collection went on display for the second time at the Bowers Museum in California  starting on June 17, 2007. The exhibition that was expected to continue for one whole year, was held in Anderson-Hsu-Tu Gallery of Bower’s Museum. Dr. Peter Keller, the president of Bowers Museum, a geologist and gemologist, and the curator of the exhibition, says, “Gems! Colors of Light and Stone” is the most important exhibition of colored stones, diamonds and gems as art, ever shown in a US Museum. What is particularly impressive is that the collection was amassed by one individual in only about 14 years!”

The Michael Scott Collection had been further expanded by the addition of several new pieces that were not found at the time of the exhibition held in 2002. All major gem species in every color and variety known were well represented at this exhibition. Besides some extremely rare varieties of gemstones were also included, such as green tanzanites, electric blue Paraiba tourmalines, red emeralds (bixbyte), and several examples of cut “collector” stones, too rare to be used in the general jewelry trade. Other exhibits included several large specimens of rough mineral crystals, and enormous gemstones being sculptured into works of art, mainly by the German gemstone carvers Bernd Munsteiner and Gerd Dreher. Silver and gold sculptures and settings for different gemstone exhibits were designed by the Seattle-based silversmith John Marshall. The 5500-carat star rose quartz mounted on its silver sculpture was again one of the most prominent exhibits at this exhibition.

Related :-

Quartz Gemstone Gallery

Quartz Cats Eye Gallery

References :-

1) Website of the Bowers Museum, Santa Ana, California.

2) Website of Art Knowledge News – Michael Scott Collection of Gems at Bowers Museum.

3) Loupe on Line magazine -GIA, Experience “Eyebytes” of Gemstone Color-Amanda J. Luke, Vol. 11 issue 1, 2002.

4) Michael Scott – Wikipedia, the free encyclopedia.

5) Star Stones (Asterism) – Dr. Barbara Smigel

6)Rose Quartz: Mineral Information Page Mineral Miners.COM

7) Rose Quartz Mindat .ORG

External Links:-

Bowers Museum

5 thoughts on “World’s Largest Star Rose Quartz – Michael Scott Collection

  1. Avatar
    stanley Tan says:

    hi i am from malaysia,recently i have discovered a rare gemstone from our state.The hardness of the stone is 7.5 to 7.8 .however our local lab name it as a carnelian,but i check the internat and i found that no record show our country have this type of gemstone.please i need your comment.thank you

  2. Avatar
    anton says:

    hi, i just mined some lavender quartz here in california…what can you tell me about it? (color and vibration are equally spectacular!!!!) color ranges from very dark pink to pure lavender (one 7 or 8 lb piece has a very pure lavender color that seems to be very unique) blessings!

  3. Avatar
    Andrew McLean says:

    Hi researching the largest gem quality rose quartz specimen in the world(I have a lovely 2.5 kilogram gem rose quartz specimen from Spitzkoppe Namibia; just wondering if it may be the worlds largest,..

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