Did you know that Opal is the birthstone of October? To celebrate this month of opal, we would like to share with you a little information about this amazing gemstone, and why we are so passionate about it here at Giulians!
What is opal, and how is it formed?
Opal is a form of hydrated silicon dioxide (chemical formula SiO₂·nH₂O). It is formed in dessert-like areas, where the geology is rich in silica deposits – sedimentary rocks like limestone or sandstone – and has strong seasonal rainfall followed by long hot and dry periods. During heavy rain the water carries the silica from the rocks creating a silica-rich solution which finds its way deep into the earth, below the water table. During the dry months the sun dries out the earth causing the water table to evaporate and retreat, leaving microscopic spheres of silica behind. This process, repeated over millions of years, slowly creates layers of the silica spheres, and this is what forms opal.
Not all the opal formed will show the spectral hues we all love. A lot of what forms is called common opal, which can be a non-descript bluish-black or milky white colour. The opal that shows the brilliant play-of-colour (or what many people refer to as ‘fire’) is known as precious opal. Most opals are cut into gems with a component of common opal or host rock still attached, as it plays an important role in the look and strength of the gemstone.
Why is it found in Australia?
The reason opal is found in Australia is due to the Great Artesian Basin. An artesian basin is an area where a body of groundwater is confined under the earth and held under pressure by surrounding layers of rock. The Great Artesian Basin is the largest and deepest artesian basin in the world, covering 23% of Australia and stretching 1,700,000 square kilometres below arid and semi-arid parts of Queensland, New South Wales, South Australia and the Northern Territory. It has a total volume of water of approximately 64,900 million megalitres.
The Great Artesian Basin was formed about 130 million years ago by a sheet of quartz over a shelf underground. Rain ran off the mountains of the Great Dividing Range creating rivers. The water on the eastern side ended up in the ocean while the water on the western side had no-where to go and just sat and sank into the earth. This process occurs every wet season and has been occurring ever since the Dividing Range was formed after heavy rains. If you look at the opal fields in relation to the basin, it is little wonder why opal is mined in these locations.
What causes the amazing colours seen in precious Australian Opal?
The rainbow colours seen in opal comes from the dispersion of white light through the layered spheres of silica. For this to occur, however, the layering and stacking of the spheres of silica need to be both uniform in size and perfectly structured. Without this structure, the result is common opal, or what we call ‘potch’ in Australia.
The stacking and uniformity of the silica spheres is not the only factor involved. The size of the silica spheres determines the range of colour seen in the precious opal. Smaller clusters of stacked spheres will show blue-greens, while the larger spheres will show the rarer colour; red. The conditions under which opal is formed generally wouldn’t allow for a lot of space, so the smaller spheres (and therefore the blue-green colours) are more commonly found. Rare and bright reds, combined with dark coloured potch is said to be the ultimate in opal. It is referred to in the industry as ‘black on red’ and will be considered very valuable.
The colour seen in opal is directional. Some opals can display a blue-green flash in one direction and orange- red in another, while others may have shifting or rolling colour flashes. It all depends on the angle of the stone and the way the light is hitting it. A stone that has bright colour in all directions will be valued higher than an opal with colour in only one direction.
The best thing about the colours found in opal is the diversity. No other gemstone has such a variety of colour, pattern and combinations, so personal taste plays a major role in which opal appeals to you!
Black Opal – Lightning Ridge, New South Wales
The most valuable of Australia’s opal is Black opal. Black opal is found in sandstone, mined approximately 20- 30 metres below the ground.
Because it forms in sandstone, a relatively soft rock, it allows for deeper deposits to form. Some of these deposits are called nobbies. A nobby is bulb shaped opal nodule found in clay which can be quite large or the size of a pea. They are tumbled to remove the sandstone, then ‘rubbed’ to allow the miner to look at the colour and quality. Nobbies are mostly mined in Lightning Ridge – which is why black opals are known for being cut into lovely high-domed cabochons. Other deposits of opal, like seam opal, occur in veins and bands and sometimes yield thinner and more irregular shaped gems.
I thought black opals were supposed to be… black!
Many people who come to view our black opals often make this observation. The truth is quite the opposite! The potch found in Lightning Ridge has a darker body colour than that of white opal – and that is where black opal got its name. The darker the body colour, the better the contrast between the common and precious opal – resulting in more vivid and striking play-of-colour in the gemstone. The black opal potch can vary from inky-black through to very light grey – the light grey tones resulting in softer colours. The potch is almost always kept as part of the finished gemstone – to provide thickness, strength and colour depth. In thicker colour bands, black opal can be cut without its potch – and this is sometimes referred to as black crystal or jelly opal.
Boulder Opal – Quilpie, Queensland
First discovered on a station south of Quilpie in 1872, boulder opals are found in a belt stretching from Quilpie to Winton in Outback Queensland. Natural boulder opal is very unique. Unlike black opal, it is formed in an area where the geology is made up of ironstone. Ironstone is a dense sedimentary rock that formed in the Cretaceous period. Due to this density, the host rock is very unyielding, so the opal formed in cracks and fissures within the ironstone. These are referred to as veins, and they can vary in thickness from fine through to thick.
Because the majority of boulder opal veins are thin, the ironstone boulder is cut as part of the gemstone – giving the opal its name. Miners split the boulders through the veins, leaving the thin opal on the surface with the ironstone behind.
Due to the reddish brown to brown-black colour of the ironstone, the play-of-colour seen in boulder opal can be very similar to that of black opal. The natural ironstone making up some of the carat weight also means they are generally cost a little less. You will also get more free-form and undulating shapes in boulder opal, as the miners have to follow the natural directions of the opal vein.
White Opal – Coober Pedy, South Australia
The name Coober Pedy is said to have evolved from a combination of two Aboriginal words meaning ”white man in hole”. Kupaka – meaning white man and Piti – meaning hole. White opal forms in limestone which, like sandstone, is a soft host rock allowing deeper seam deposits to form. The body tone of white opal is much paler, so the play-of-colour seen is more bright pastel hues. It is not uncommon for white opal to be cut without its potch which means the opal play-of-colour will be seen from the front and the back.
I hope you have enjoyed learning about the geology and origins of Australian opal in Part 1 of our Opal Discovery! In part 2 I will be looking more in depth at the colours and patterns found in opal, and the differences between them. If you have any questions about opal or would like to know more about our opals, please get in touch by using the form below or emailing us firstname.lastname@example.org.
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Giulians 2nd Meet the Brewer and Putt for Cash evening was a great success! Congratulations to Allan Alvarez – the winning putt of the evening!
Thank you to all who attended and for those of you who couldn’t make it- here are some of the highlights.
So what happens when 2 American-born lacrosse players with a love of homebrew, meet halfway across the world? They open a brewery in Sydney of course! In 2013 Andrew Fineran and Chris Sidwa opened Batch Brewing Co, transforming an old panel-beaters workshop space in Marrickville into a brewery and tasting room – complete with polished concrete, black walls, mural art and an ethos of ‘we brew for you‘. And brew is what they do.
Batch Brewing Company brews beer the traditional way, handcrafted and batch by batch. Apart from a few regulars, the range changes every few weeks – so each batch is a limited release. If you head to Batch Brewing Co’s website you can check out each their batches, past and present (all 169 of them!)
You can drop in to taste the latest batches and take home a growler (1.89L), a bomber (640ml) or a 4 pack (440ml cans) filled with the beer of your choice. Batch also offer private brewery tours, where they will show you around, and share the science and art behind each Batch. Tours are on Saturday and Sunday at 12:30pm and 2:30pm by booking only, so email email@example.com for more information and to book in.
Tom Walker of Batch Brewing took us through some beers on the evening. Four beers were for tasting – American Pale Ale, Trippy Hippie’s Voodoo Gold, Pash the Magic Dragon and Elsie the Milk Stout. Scroll down for tasting notes and other information on each beer!
Thanks again to everyone who came along, and we look forward to seeing everyone at our next Meet the Brewer night (or maybe something different), which will be on Wednesday 14th November. The pot will be reset to $500!
Please email firstname.lastname@example.org if you would like to know more about our next event, or if you have any feedback, comments or questions. We would love to hear from you.
We went on a road trip!
Last month, Gary, Trina, Joel and I took a day off work, and drove down to Canberra, to see Cartier’s exhibition of historical jewels on display at the National Gallery of Australia. Established in 1847 in Paris, by Louis-François Cartier, Cartier is today an internationally recognised jewellery and watch manufacturer.
Famous for their garland style designs from the early 1900’s, it is of little wonder Cartier became known as the ‘Jeweller to Kings’ – creating tiaras and ornate adornments for aristocrats, socialites and royalty.
Cartier was heralded as a pioneer in the Art Deco style – their early use of minimalist and geometric shapes in their jewellery predated the First World War, and continued well into the 1930s.
During the late 1940’s the panther motif was introduced to their collection and became a quintessential Cartier symbol across their entire range, known as the Panthère de Cartier. From pave sections adorning handbag clasps – mimicking the spots of a panther, to the three-dimensional panther brooch owned by Wallis Simpson (The Duchess of Windsor), the Panthère de Cartier collection has had many famous advocates – and is still going strong today!
Wandering through the exhibition, it was interesting to see how the motifs evolved over the decades, and to see where the designers drew their inspiration from. The archaeological exploration of Egypt, travel of the Royal family to India, and the art of East and Southeast Asia opened up an exotic source of inspiration, which they applied to all sorts of creations – cigarette cases, jewellery, clocks and watches.
Over 300 pieces were on display – a combination of Cartier’s collection and loaned pieces from private collections worldwide. The jewels of Grace Kelly (Later Princess Grace of Monaco), Elizabeth Taylor, Sir Elton John and the Royal family were part of the exhibition.
Before heading back to Sydney, Joel and I stopped at Lerida Estate Winery opposite Lake George, for a late lunch and a glass of their pinot rose. When a winemaker compares the colour of their wine to an Argyle pink diamond, you know they have taste!
Scroll down to see a few more images taken on our journey.
Visiting Sydney soon? You may have already researched where to eat during your stay, but sometimes a brilliant wine list can help make the decision easier!
The Annual Wine List of the Year Awards, held last month, is the Oscars for restaurant owners and sommelier’s wine lists as they learn how their carefully constructed list stack up. 2018 was the 25th year of this award.
The most important part of the night is the all important “Glass” rating where restaurants find out if they have received 1, 2 or 3 Glasses, just as they do with “Chefs Hats” for their chefs creations in the kitchen. Sydney is proud to boast 55 restaurants awarded with a 3 wine glass rating.
In addition there are dozens of other categories that cover individual states, city / country, by the glass, beer, sparkling, aperitif, digestive, wines from each state, to read the full 2018 list click here. Scroll down to see the list of Sydney’s 3 Glass restaurants and the National Award Winners.
SYDNEY 3 GLASS RESTAURANTS
Altitude, Aqua Dining, Aria Sydney, Ash Street Sydney, Balcon by Tapavino, Balla, Bambini Trust, Banksii Vermouth Bar, Bar H Dining, Bennelong, Bentley Restaurant, Bert’s Bar, Bibo Wine Bar, Cafe Sydney, Catalina, Century, Cirrus, Cut Bar and Dining, Dear Saint Eloise, Devine Food and Wine, Dolphin, Felix, Flying Fish, Fred’s, Fujisaki, Glass, Golden Century, Hubert, Icebergs, Love Tilly Devine, Manta, Momofuku Seiobo, Monopole, Mr Wong, Nomad Sydney, One Ford Street, Ormeggio, Oscillate Wildly, Pendolino, Pilu at Freshwater, Prime, Public Dining Room, Quay, Rockpool Bar & Grill, Rosetta Sydney, Royal Sydney Yacht Squadron, Sake The Rocks, Sokyo, Sixpenny, Spice Temple Sydney, Tetsuya’s, Uccello, Wine Library, Yellow
NATIONAL AWARD WINNERS
BEST WINE LIST – Aria Brisbane
BEST NEW LIST – Dear Sainte Eloise
BEST SMALL WINE LIST (MAX 100 WINES) – Chiswick
BEST LIST BY THE GLASS – Bentley Restaurant
BEST SPARKLING LIST – Aria Sydney
BEST APERITIF – Devine Food and Wine
Excerpts from original article by Alsaker.com.au
Giulians inaugural Meet the Brewer and Putt for Cash evening.
Everyone’s heard of food and wine pairings – even food and beer pairings, but beer and fine jewellery may not seem such an obvious match!
Most of you know what we do, and how well we do it, so Gary’s idea for this bi-monthly event is simply to create a fun experience – an introduction to a local Sydney brewer, while adding a competitive edge with a putting competition and a chance to have some laughs.
For those lucky enough to attend, you already know it was a bit of fun, but for the rest of you – here’s a glimpse of what you missed and what you can look forward to next month. Keep scrolling for all the images taken on the night.
Wayward Brewing Co.’s ethos is ‘life is about finding out what’s around that corner, experiencing new things and enjoying great beer with good friends’. When you find people passionate about what they do, it is easy to share in their enthusiasm, and Pete Philip, founder of Wayward Brewing Co is no exception.
Pete, combining his love of beer, business, travel and adventure founded Wayward brewing Co in 2012. Wayward by name, the company was a gypsy brewer until 2015, when Pete, along with head brewer Shaun Blissett opened Wayward’s 1st brewery and cellar bar at 1 Gehrig Lane, Camperdown. This was originally the site of a winery, dating back almost a century. The original wax-lined wine vats have been converted into rooms, and with a 24-tap bar featuring both Wayward’s core range of craft beers and some constantly changing single-batch seasonal releases, it is a beer lovers paradise. (A small wine list for the non-beer drinkers). They also do brewery tours on Saturdays and have a rotating food truck schedule and pizza menu, so it is totally worth a visit! For more info check out http://www.waywardbrewing.com.au/
Pete generously lent his time on the night to talk about his beers and his brand.
Four of Wayward Brewing Co’s beers were for tasting – a Bavarian lager, a pale ale, a sour beer and a dark IPA.
KELLER INSTINCT – Bavarian Lager
Kellerbier is a German style of beer which literally translates to ‘Cellar Beer’ – referring to the cooler temperatures the beer is brewed and conditioned under.
Notes: A pale-golden, Bavarian Lager which uses premium German, Wheat, Vienna and Munich malts, giving a sweet, biscuit flavor and an ultra-smooth finish. The Wheat specifically adds body while the hops give a touch of herbal notes. This beer is cold fermented, giving it that crisp, clean finish. 4.8% ABV
CAMPERDOWN 1 – Pale Ale
Notes: Named after Wayward’s neighbourhood, this is a guaranteed crowd-pleaser. This smooth and easy drinking golden summer ale has just the right balance of biscuit malt and fresh hop aroma that melds the best of an American and English ale style. Pine on the nose gives way to passionfruit on the palate and a light, fruity finish. It acts as an ideal food pairing and tastes good with just about any dish. 4.6% ABV
SOURPUSS – Raspberry Berliner Weisse
Considered the “champagne of beer”, this tart, fruity wheat beer is a traditional Berlin-style sour with fresh raspberry aroma and a light sweetness with a clean pilsner and wheat malt finish. Sourpuss is an ultra- refreshing beer that is perfect on a hot summer’s day or paired with food. A great choice for both cider lovers and beer lovers. First brewed by request of Pete’s wife and now a fan-favourite among Wayward punters. 3.8% ABV
SLAPSHOT – Dark IPA
The Slapshot Black IPA is a traditional hop forward American IPA brewed with dark roasted malts. These bold malt flavours of caramel and cacao balance perfectly with the citrus-fruit and pine hop character, to give a smooth and rounded finish. 6.5% ABV
Despite some admirable attempts, no-one made the winning putt – during the official part of the evening at least. (Apparently if you remove the pressure of cash and add more beer, putting becomes easy!) But this means the prize has doubled! So with that incentive in mind – come and try your luck next month.
Thank you to all who attended. To sum up the night, I think Phil said it best –
Thank you for arranging such an enjoyable evening for us all- great beers, great conversation, some lovely opals & some mediocre putting.
We look forward to seeing even more faces at our next Meet the Brewer night, which will be on Wednesday 5th September (mark it in your calendar!) Please email email@example.com if you want to know more about Giulians or our next event.
Ever wondered what Gary gets up to on his days off? Golf, gardening and… this!
Last year Gary was tasked with making a commemorative plaque for a friend’s retirement. Using some specimen grade ‘boulders’, Gary got on the power tools in his front yard. His youngest son Liam, who is a keen photographer, captured some fantastic photos during the process.
We hope you enjoy this gallery of images showing the transformation of a lump of boulder opal rock into a gorgeous retirement gift, presented to Mr Ron Greedy, a longtime member of Les Clefs d’Or Australia. Celebrating 22 years of ‘Service Through Friendship’ – Congratulations Ron!
Handmaking a Pink Diamond Pendant.
When we aren’t busy making beautiful pieces for clients, we are creating new pieces for our boutique. Recently inspired by a lovely pink diamond and geometric shapes, Gary designed this 18ct white gold pendant. I hope you enjoy this gallery of images, capturing the evolution of this one-off piece.
Thanks for viewing! If you are interested in this piece or wish to learn more about Australian pink diamonds, please get in touch with us via email firstname.lastname@example.org or by filling out the form below.
What colour is a sapphire?
It is a simple enough question. The mere mention of the word sapphire brings to mind the colours royal or cornflower blue – like Princess Diana’s famous sapphire ring, now worn by Kate Middleton – The Duchess of Cambridge. What many people don’t realise is that sapphires come in almost every colour imaginable – blue, green, yellow, purple and pink.
Gary recently received a bespoke order from a client for a pink sapphire ring, with the view to also create a pair of matching earrings and pendant. We always start these enquiries by finding the perfect gem. Even after 40 years of experience, Gary was surprised by how challenging finding the ‘perfect matched set’ would prove to be.
Peach, apricot, salmon, coral, purplish pink, cerise, amaranth, fuchsia, watermelon, hot, lolly, dusty, mushroom or baby pink? Even the names are a challenge! The colour ‘peach’, for example. Does this refer to the skin colour of the stone fruit, which varies from dark pink to orange, or the inside flesh which is more on the orange side? And what makes a pink sapphire a ‘Padparadscha’.
See the gallery below for a small insight into the wonderful world of pink sapphires and the sometimes challenging (but always fun) creative process!
Gaining popularity at the moment is a very rare and special colour in pink sapphires called Padparadscha. This is the name given to sapphires that have both pink and orange tones present. The original Padparadscha sapphires were found in Sri Lanka, however other deposits have been found in Madagascar, Vietnam and Tanzania. The word Padparadscha is derived from the Sinhalese word meaning lotus blossom, and the colour of these sapphires has been described as somewhere between a lotus blossom and a sunset.
If you would like to find out more about Padparadscha sapphire or any other sapphires, please feel free to contact us on email@example.com or by using the form below.