Posts by admins

    Dear Mr. Fitzgerald.
    Thanks for your inquiry about copyright issues involving the image of the "Blue Giant of the Orient" appearing in our blog webpage of the same title, written on March 11, 2008. The image obviously came from the Christie's website when the stone appeared at their Geneva Magnificent Jewels Sale held on May 19, 2004 and probably also appeared in one of their press releases. Our site is also an educational website and we had published several images from Christies auction catalogue, without any problems.
    Thanks for your inquiry. Please keep in touch.
    Dr. Shihaan Larif

    Hello "tentate",

    Welcome to our forums!!!!

    We will take a closer look at the photos and answer your post within 24 hours.

    Meanwhile please join our facebook page (Click like at the bottom of this page-Floatbar). Please invite all your friends on facebook to our page.

    Thanks in advance

    The following is a question raised by one of our readers pertaining to our Blog webpage on "The Black Star of Queensland Famous Black Sapphire Gemstone"published on February 19, 2008.
    After reading the article on the Black Sapphire of Queensland and the amount of money that it brought in 2002, I wanted to ask Dr. Shihaan of his opinion as to what the “Black Sapphire of Queensland” would be appraised for today?

    The following answer was provided by me on April 1, 2009 :-
    Thank you very much for the question regarding the black star sapphire.
    Actually it is not known for how much the stone was sold by the anonymous owner in 2002.The estimate of 100 million dollars was quoted by several leading newspapers, but they did not quote their source either.
    Considering the enormous size and the perfect star, I am not surprised at the estimate.
    Take a look at the current prices of black star sapphires:These are the prices of smaller black star sapphires.
    >1.0carats 3 to 10 US$ per carat
    >1.0–4.99carats 10 to 50 US$ per carat
    5.0carats + 30 to 100 US$ per carat (golden stars may reach US$ 200 per carat).
    The Black Star of Queensland is the only large black star sapphire in the World, it is the only one of its kind in the world.There are numerous large star rubies and large star blue sapphires in many museums and private collections of the world.
    The usual sizes of black star sapphires is less than 5 carats, making the black star of Queensland an extremely rare gemstone.It is highly unlikely that another one of this size will be found even in the future.
    In my opinion it is difficult to estimate the present value, being an extraordinary stone it cant be compared to market value, because black sapphire stones of such enormous size and quality are not available in the market. The price will be determined by the highest bidder (auction) for the gemstone.
    Please feel free to contact me if you have any further questions/comments on this gemstone or any other gemstones/diamonds - Dr Shihaan

    Assaying is defined as the testing of precious metals to determine their purity.
    The precious metals usually referred to while assaying jewelry are sterling silver, gold and platinum.

    After assaying, the article is "Hallmarked" to confirm the purity of the metal. Hallmarking
    involves punching with three or four symbols, each symbol giving specific information.

    Hallmarking jewellery gives confidence and assurance to the buyer of the standard of purity of the
    precious metal.

    The assay office in Sri Lanka was established in October, 1981. It sent officials to the London Assay Office to up-date their assaying techniques. At the moment the assay office is based in Colombo at the National Gem and Jewellery Authority office complex. They are hoping to open two new branches in Galle and Kandy.

    The Sri Lanka Assay Office is a member of the European Assay Offices whose head office is based in Geneva, Switzerland. The assay office in Sri Lanka also has plans to join the hallmarking convention.

    The services of the assay office is open to anyone who may or may not be in the jewellery sector. The assay office also issues certificates after assaying and hallmarking.
    The Sri Lanka Assay Office Address
    The assay office is situated at the headquarters of the National Gem and Jewellery Authority
    25, Galle Face Terrace, Colombo 03.
    Tele: 2325364, 2329295,2320758, 2390645-8.

    The charges for assaying are found at the following link to their website:

    Analytical techniques used at the Sri Lanka Assay Office.

    1. Cupellation method ( fire assay)
    2. Potentiometric titration
    3. Atomic absorption spectrophotometry
    4. X-ray fluorescence spectro metry

    There are some registered jewellery shops around the capital Colombo that sells hallmarked jewellery.

    The standard of purity of precious metals is indicated by specific numbers and the order in which the symbols are stamped in a piece of hallmark jewellery, is as follows:

    Precious Metal Purity or Fineness

    Sterling Silver 925 916 750 375

    The authorized standards of fineness in respect of gold, silver and platinum are given below:


    999PPT corresponding to 24Kt.
    916.6PPT corresponding to 22Kt.
    875PPT corresponding to 21Kt.
    750PPT corresponding to 18Kt.
    585PPT corresponding to 14Kt.
    417PPT corresponding to 10Kt.
    375PPT corresponding to 09Kt.
    333PPT corresponding to 08Kt.


    assay office mark,
    gold/platinum mark,
    numerical purity value and
    manufacturers mark.

    Sterling Silver
    assay office mark,
    sterling silver mark,
    numerical purity value and
    manufacturers mark.

    This was a question on the Golconda-D Diamond, a C2 comment which was transferred to this page.

    Do you know if this diamond was ever graded by a lab? If so, do you know its fluorescence rating?

    Richard Wise

    The following are comments by visitors to our webpage on the Amarillo Starlight Diamond published in 2007 :-

    Can you tell me who currently owns the Amarillo Starlight? Or a way for me to find out?


    Ocala, FLorida

    Answer by Rob. S

    I'm the finders (W.W.Johnson's) Grandson.

    It was cut into a smaller diamond and sold in NY.

    The buyer was not revealed to us, as far as I know.

    My family owns the smaller pieces which were made into smaller stones.

    Thank you for the interest in my Grandad's find

    The following is a comment made on our webpage "The Grand Duchess Vladimir Tiara."

    I have only just found the site, and love it. Thank you.
    I have one question, you state that Queen Elizabeth gave the Vladimir tiara to Princess Diana, and that Diana often wore it. I am sure that this is not correct.
    The Queen did give Diana the Cambridge lovers knot tiara, which she inherited from Queen Mary, and Diana indeed did wear it often. Not the Vladimir though, of this I am sure.

    by Norma

    Lancashire, England. I.P. address:

    This page was moved from content 2 to here.

    1)The per carat weight of a stone increases exponentially when the total weight of the gemstone increases.For example if the price of a 0.8-carat gemstone is 100 usd. Then a similar 3.5-carat gemstone of the same quality (similar physical properties like colour,transparency etc) might cost as high as 3500usd.

    2)Gemstones that have extraordinary properties such as colour change under different types of light are more expensive than gemstones that do not have this property. Examples of gemstones that have this colour change property is alexandrite and some garnets. The colour change may be more prominent in some gemstones than others. The more prominent the colour change the higher will be the the price.Prices of gemstones that have the colour change properties can be even higher than rubies.

    3)Treatment done on a gemstone also influences the value. Usually it is the totally untreated gemstone which has the most value.Examples of different types of treatment are heating,radiation,diffusion and oiling.

    4)The colour of the gemstone also determines the price. eg among sapphires, various light tints of pink, yellow, mauve, green and white are referred to as "fancy sapphires". Generally fancy gemstones have much lower value than their counterparts.

    5)Chrysoberyl cat's eye gemstone comes in different shades of honey, apple green, dark grey and brownish yellow. The valuation of chrysoberyl cats eye is similar to the valuation of star sapphires( see below). In cats eyes it is the clarity of the "streak of light" that determines its value.

    6)Among star sapphires and star rubies, a simple classification into four categories will help the valuation. This classification is based on the clarity of the star and the colour of the background:

    a) The star shows clearly in ordinary light with background colour that is either deep blue (star sapphire) or deep red (star ruby). These are regarded the best and command the highest prices in this variety.

    b)The star is only visible in strong light but with a good background colour.

    c)The star is visible in ordinary light but with a dull or weak background colour.

    d)The star only shows clearly in strong light and there is an extremely weak background colour.

    7) The presence of cracks, flaws and inclusions can decrease the value of a gemstone. In some gemstones such as rubies, the presence of small amount of inclusions is acceptable because it is proof that the gemstone is "Natural".

    8)Rarity of the gemstone will be of value even if it is not commonly used in jewelry. Examples of rare gemstones found in Sri Lanka are: Ekanite, Sapphirine, Scapolite, Sinhalite and Taaffeite. These gemstones have "collector's value". Gemmologists, geologists and mineralogists all over the world collect such gemstones. Museums , Universities and research centers around the world also collect these gemstones.

    Summary of the principles of valuation in general

    1)Demand for the item.

    2)Supply of the item.

    3)Scarcity of the item.

    4)Durability of the item.

    5)Brand and Design of the item

    Summary of the principles of valuation of gemstones

    1)Appearance to the human eye(eye catching beauty- Probably the most important)

    2)Physical properties of the gemstones such as colour, clarity,flawlessness,proportions,transparency, weight of the stone and the type and quality of the cut.

    3)Rarity of the gemstone with respect to other types of gemstones.

    In this post I will deal with the aspects of valuation that are relevant to gemstones, jewelry and diamond industry.

    The principle of valuation of gemstones is similar to the valuation of any item (as outlined above). A rare gemstone(such as alexandrite or emerald) is more expensive than a common gemstone (eg Topaz), which
    is comparatively cheap.

    Probably the most important aspect of the valuation of gemstones is the beauty assessed by the
    human eye (eye catching beauty). This eye catching beauty cannot be assessed by any machine.In
    other words when a gemstone is offered for sale, it speaks for itself.

    The physical properties of the gemstone that are important for valuation ,are intensity,
    transparency,clarity, flawlessness,proportions,quality of cutting,standard of polishing and weight
    of the stone etc.

    The internationally accepted unit for weighing gemstones is the "carat". A carat is equivalent
    to 1/5th of a gram (200 milligramms or 0.2 gram). The word "carat" comes from the seed of the carob tree
    (Erythrina Ceratonia Siliqua) which grows in Africa. The chocolate brown trees of the carob
    tree are flattened with a pear-shaped appearance. The dried seeds of the carob tree show a constant
    weight in any season of the year which is equivalent to 200 milligram or 0.2 gram.

    According to D. H. Ariyaratna (FGA, DGA, FGS):

    "The value of a gemstone can be defined as purely an opinion of the individual valuer given in
    good faith and expressed in monetary numerical terms,based on the prevailing market price per
    carat at the time of valuation"

    Gemstones, just like any other commodity is subject to constant variation in the value due to
    numerous factors.Therefore the precise valuation of a gemstone is impossible.

    More information to follow in subsequent posts.

    I will answer this question in two parts. In this post I will deal with the first part, which is "The principle of valuation in economics".

    The valuation of gemstones or any other item or commodity (eg Rice, shoes) are based on the same basic principle that is common to any item or commodity.Some aspects of valuation that are specific to gemstones will be dealt with in the following post.

    In the study of economics we come across some basic principles such as scarcity, supply and demand.
    The combination of these factors determines the "Price of an Item"

    In this post I will discuss the most important concept that is behind the valuation of any item.
    This is the concept of demand and supply.When demand equalls supply the price is called the "equilibrium
    price", or more commonly "the market price".Generally if the demand exceeds the supply,the
    price increases. When the supply exceeds the demand,the price may come down.

    It is the combination of many factors, one of which is demand and supply that lead to the value
    of an item.

    The demand and supply concept can also be coupled with the "scarcity concept". There are
    some items that are generally more scarce than others. The more scarce an item is the higher
    the price. It is an accepted fact that gemstones are relatively scarce.

    Another very important factor in economics that determine the value of any item in the market is durability.
    The more durable an item, the more will be the price.Quality is another important aspect
    of valuation. Quality and durability may not necessarily be the same. Quality is more appropriate
    for functioning or working items.

    The Brand and design (Which may or may not be associated with durability) is also an important
    factor that determines the value of an item.

    I was in the "Luster Exhibition at the BMICH, Colombo" when I came across the Gem and Jewellery Institute Stall. Its a pity I did not know about it all these years. Apparently it was established in 2002.

    The following is from their brochure, which they were distributing at the show.

    The Gem and Jewelley Institute (GJI) is the foremost center for vocational training in Jewellery Design, Manufacture & Lapidary training in Sri Lanka.

    Based on a recommendation by Peter Raw, a consultant for the UK based World Gold Council in 2000, GJI was established with equity participation from eleven leading private sector jewellery manufacturing exporters and retailers, four state sector institutions and the apex trading association, with the aim of imparting a high level of education and training to students, and thereby enhance the product quality of Sri Lankan jewellery and expanding its scope in the domestic as well as international markets.

    GJI,a non profit organization committed to excellence in education, is one of its kind in the country's educational set up. One of its objectives is to encourage the youth of today to seriously consider the option a career in the gem and jewellery industry.GJI also imparts the necessary knowledge and techniques for professionals who are already in the industry to compete in the global market place. Over the past few years the institute has made substantial progress towards satisfying the industry's demand for skilled professionals.

    The GJI is assisted by two state agencies, the National Gem and Jewellery Authority(NGJA) and the Sri Lanka Export Development Board(SLEDB). The National Gem and Jewellery Authority provides sponsorships for students enrolling in GJI education programs, which is of immense value to both students and firms in the industry.

    Since its inception in 2002, GJI has been working with two principal donor agencies in realizing its goals,upgrading the sector and serving the country at large.

    In 2005 GJI received Technical Assistance from USAID funded "The Competitiveness Program"(TCP) to sponsor trainers from the Texas Institute of Jewelry Technology (TIJT). From 2005-2007 the institute received sponsorship from the European Commission (EC) in Capacity Building and skills development of the sector with the Technical Assistance from the prestigious University of Central England. In 2007 the GJI received Technical Assistance from the USAID funded TCP in building up a Lapidary School in the institute.

    At present located in the heart of Colombo, the institute has fully equipped facilities in Jewellery Designing, Manufacturing and Lapidary. The courses are conducted by a panel of highly talented practitioners with considerable local experience and foreign education. The institute is governed by a group of 10 professionals representing the industry in Sri Lanka.This active participation of the industry in managing its affairs is looked upon as the biggest strength og GJI.
    Looking back at its short span of history, GJI has a humble pride of being able to add value to the sector and contribute to its growth.

    With a glance at the future, the GJI sees itself as a nationally reputed, regionally recognized full-fledged vocational training institute offering quality assured, sector specific training in all aspects from Designing to Management and Marketing.