Sotheby's sale of Magnificent Jewels in New York on 14 April promises to be an interesting event. Our jewellery expert had a good look and feel at the preview in London this week and came back with the following gems of information - and favourite piece is a Paul Flato feather brooch. "To spice things up a bit, there is a nice story to this sale that includes jewels from a private collection amassed by two generations of women, one collecting in the 1920's and 30's and the other in the 1940's and 50's . Both clearly had magnificent taste in jewels and a bank balance to match. There are also some very pretty pieces of jewellery, notably Cartier, that will be appreciated by today's collectors. Amongst these interesting vintage pieces there are some fine examples of old diamonds that were cut for candlelight. And what's more, not only is there an array of white diamonds but also a yellow as well as favourites of the moment: both a blue and a pink. Eyes will be focussed on the ruby with a high pre-sale estimate of $800,000-$1.2 m. The Egyptian Revival necklace (Lot 66) estimated between US$40,000 to $60,000 is not only a beautiful jewel, what is so nice about it, is that unbeknownest to the onlooker it is all carved on the back with Egyptian motifs. But we don't just look at jewels, we have a good feel too so can confirm that this piece has a nice weight, unlike modern jewels that can feel flimsy. Lot 184 is a 'Golconda diamond' 5.2 carats (est US$600,000-800,000) and platinum ring. This looks like the original old-cut with a flat, spread out shape that is quite rare to find. The unusual cut was probably determined by the shape of the rough. It has a wonderful watery feel about it, which is what Type 2A or 'Golconda' stones are known for and gives a diamond a softer sparkle - less harsh than D colours. Only 1% of world diamonds are classified as Class 2A (or Golconda) because of lack of nitrogen in the carbon structure, the element which gives diamonds their yellowish hue. Lot 186 is a Kashmir sapphire ring, 6.61 carats (est US$125,000-150,000) that is from the Kashmir mine, the best source for sapphires. The stone is a characteristic deep rich, velvet colour, not a sharp blue hue. Kashmir stones always look hazy and the tone to look for is cornflower blue. Kashmir sapphires are rare as not only is the mine some 30,000 feet above sea level, and very inaccessible but it is also virtually extinct, making these stones even more valuable. Lot 187 Schlumberger for Tiffany Fancy Vivid yellow diamond (11.13 carats) ring from 1972 (est $500,000-700,000) is beautiful jewel framed by diamond bees on the shank. Schlumberger began designing jewellery in the mid-1930's but his collaboration with Tiffany, starting in 1956, sealed his fame. There is always a nice substantial feel to Schlumberger's jewels as he made sure there was a good weight to his pieces and wonderful attention to detail. And this yellow diamond is a vivid which makes it a lovely colour and highly sought after. Lot 260 Gold, platinum and diamond Feather brooch by Paul Flato circa 1940 (est $15,000-20,000) & Lot 330 Platinum and diamond brooch possibly designed by Verdura for Paul Flato (est$30,000- $50,000) What is so beautiful about these pieces is that they are about 5 inches long, almost the length of your hand and each one of the feather whisps is articulated. If I had some money, I would buy these brooches. They are stunning and beautifully made. You could wear  one alone or both together up the side up of your shoulder for a very 1940's look. Flato, from Flatonia in South West Texas that was named for his family, designed jewellery for all the 40-50's Hollywood actresses such as Greta Garbo and Marlene Deitrich and had a salon in Beverly Hills. He helped create the American Dream with escapist jewellery that was seen on the silver screen around the world. Lot 332 Raymond Templer bangle bracelet and brooch (est $90,000 - $110,000) combination was made in France circa 1935. The top of the bangle comes off to form a brooch. Templer is known for his geometric compositions inspired by modern technology and the age of machine. I think it is rather nice to see a piece of jewellery with such a strong architectural style of the period. Much excitement around Lot 337 a Fancy Vivid pink diamond ring (est US$1.5-2 million). Pink and blue diamonds are commanding the highest prices at the moment. This one has a nice clarity (VVSI ) which is notable as a lot of coloured stones can be flawed and this one is not. The stone has been re-cut into a new cushion shape and is 3.64 carats. Old cushion shapes had less facets and the angles of the cut were less uniform giving a softer look. At the moment it is the Graff pink that holds the record. It was auctioned by Sotheby's to Laurence Graff in November 2010 for $46.1 million, or $2 million a carat. Lot 343  Burmese "Royal Blue" sapphire (24.6 carat) ring (est US$700,000-1million). This stone has an electric blue colour and lots of life and radiance hence it is known as "royal blue". Lot 352 is a rare site: JAR diamond and emerald earrings (est US$100,000-200,000) . They are a fine example of this mysterious jeweller's work. The earrings are so flat and thin that getting all those old-cut marquis diamonds and emeralds to sit on there is a lot of hard work. The earrings sit well on the ear because they are so flat and light. It is very rare to find a JAR piece at auction, reflected in the estimate and these earrings are a good example of discreet and very sophisticated jewellery. Lot 357 is a ruby and diamond brooch by Chaumet from 1920 (estUS$800,000-1.2 million) . Under incandescent light they will look fabulous which is why rubies are at their in candlelight. The estimate is high for a ruby so watch this space and see what the market makes of this rare 10 carat ruby with a magnificent colour. Lot 360 is a Fancy Vivid blue diamond3.18 carats set in a brooch (est $3-4 million).   The record for a blue is the Bulgari Blue sold by Christie's for $15.7 million, just under $1.5 million per carat. The stone has an  excellent symmetry and polish and one below flawless, which is particularly rare in an unforgiving emerald cut. Lot 369 (est $20,000-30,000) & 370 (est $12,000-15,000) are Cartier 1940's sapphire and diamond flower brooches and ear clips. I love the subtle colour combinations of these jewels that came from a private collection of two different generations of women from the same family. And finally, Lot 383, a 30.52 carat D colour VVS 1 emerald cut diamond (est$3-4 million). This diamond would have started off at more than 60 carats of rough. Let's watch how the market reacts to this rare diamond, though my hunch is that coloured diamonds are the hot ticket of the moment."