The 4Cs in relation to diamonds is a good place to start, what are they?
Emma Clarkson Webb: Every diamond is graded systematically according to the ‘4Cs’: cut; clarity; colour; and carat (or weight). These are the characteristics that determine its price. The clarity grade, for instance, has the biggest impact on price, but the least impact on the stone’s physical beauty.

Rachael Taylor: For a traditional white diamond, the standard of excellence is an ideal cut, no blemishes and a bright white colour. Diamond grading is on a scale, so the closer you can get to perfection, the higher the price. As for the size – or carat – of a diamond, it’s the bigger, the pricier. Bear in mind that 1ct is a popular size, so there tends to be a big jump in price from a 0.9ct stone, but really it would be hard to tell the difference with the naked eye. Everyone has different priorities – some want size, others want a really white diamond so it’s important not to see the 4Cs as a hard and fast rule. They are a guide to quality and price, but nothing beats looking at a diamond and deciding for yourself how it makes you feel.

Can you tell us a bit more about different cuts of diamond?
Emma: The most popular diamond is the round cut. It is the only stone cut with numerical precision, which gives it exceptional brilliance. But it is also the most expensive. The second most popular is the cushion cut: it’s an antique cut that has a truly romantic and classic look that stands out.

Rachael: Other popular options include Asscher cuts, pears, marquise, ovals and princess cuts.

And what about the ring?
Emma: The metals vary as much as the stones too. Yellow gold is obviously classic, but white and rose gold are very popular. Platinum is always popular. White gold is a bit cheaper than platinum but the colour wares off over time so the ring needs redipping from time to time.

Rachael: Platinum and 18ct gold are the strongest precious metals, so will put up with daily wear and tear.

How do you know that the stones are legit?
Emma: Every non-antique stone comes with a GIA certificate and serial number to prove it’s authentic and that it was ethically mined. The serial number is engraved on the diamond, but isn’t visible to the naked eye.

Does an engagement ring have to have a diamond?
Rachael: Absolutely not. Coloured gemstone engagement rings are enormously popular, particularly different shades of sapphire or rubies. Just be aware that, if the ring is intended for daily use, some gems are not hard enough to withstand too many knocks. If your intended is a little heavy handed, perhaps avoid emeralds, aquamarines or opals.

Where should you go to buy the ring?
Rachael: You can find antique options in auctions or specialist jewellers like Susannah Lovis, or you can head to the high street if you want a simple design. If a brand name is important to you both, head to the likes of Tiffany & Co, which has engagement rings from £2,000, but you are of course paying for the name, not just the diamond so if size is important then you might be better to have something made from an independent such as Richard Warrender from W&W. It will also mean your ring is unique. You can also find great prices on diamonds online, where options such as Taylor & Hart let you virtually customise a ring for stylistic and budget purposes.

What else is important?
Rachael: Keep your wits about you. Go in with a lot of questions: is it good quality? Are the diamonds certified? Can you trust this dealer? Is it hallmarked? Is there are returns policy? Word of mouth is a good place to start.

What’s the rule these days on how much should you spend?!
Emma: There are so many clichés about spending three months’ salary and the like, but these are gimmicks created by the big brands. Spend enough that you feel proud of what you’re buying, but don’t spend too much that you can’t go on honeymoon!

Rachael: If it’s not a surprise proposal, this is perhaps a conversation the two of you should have together. This is a ring she will wear for the rest of her life, so it is not an area to skimp on in the wedding budget. The cake will be forgotten in a flash and the dress will likely only make a single outing, but the ring is something she will look at every day. You want her to love it, and for it to be a ring that will grow with her - a speck of a diamond on a wispy band might be cute now, but how will that look on her finger later in life? Just don’t forget to hold some budget back for the wedding rings – people often forget about them and they’re just as important.

Is there room for negotiation on prices?
Emma: In some instances, there will be room for negotiation on, say, the stone. If you don’t ask you don’t get.

Rachael: It very much depends on what you are buying and from where. Haggling might be encouraged in some places, while others will have fixed prices. An alternative route to getting the price down, if negotiations have failed, is to tweak the existing design. There are lots of options here, such as swapping the diamond for one of a slightly lower grade or going for a thinner band that uses less metal. If the overall size of the ring is important then the ‘halo effect’ whereby you add a ring or two of diamonds around the stone is extremely effective as small diamonds are pretty expensive and the end result is stunning.

You could also opt for a lab-grown diamond instead of a mined diamond. These manmade stones are becoming much more prevalent. They are gemmologically and visually identical to diamonds extracted from the ground and graded in the same way, but around 30% cheaper. They are not fake diamonds – think of them as farmed salmon versus wild salmon. You can also buy lab-grown coloured diamonds, such as blues and pinks, for a fraction of what the mined equivalent would cost. Other alternatives for the diamond look are white sapphires, topaz or zircon, but they most likely won’t have the fire and brilliance of mined or lab-grown diamonds.  

How far in advance should you buy the ring?
Rachael: If you are buying off the shelf, you can leave it a couple of weeks before the proposal. If you want to commission a ring, you’ll need three months to work through the concept with the jeweller and allow for its bespoke creation.

So how do you get the finger size right?
Rachael: Try and get one of her other rings for comparison. Make sure it is a ring that she wears on her third finger to get an accurate sizing. Take it into a jeweller or measure it against a ring sizer. There are lots of free tools online.

Emma: It’s surprisingly easy to make an educated guess on finger size once you ask a few questions and see some photos. A resize after the proposal is also very quick and easy.

Do you have to take out insurance for a ring?
Rachael: This is likely to be a major purchase, and it would be devastating if it were lost or stolen. Diamonds have a long history of increasing in value over the years, making them an ideal investment and definitely worth insuring.

Finally, what happens if she doesn’t like it?
Rachael: It’s going to hurt, but it’s best to get all this out in the open. There’s nothing worse than having to wear something every single day that you don’t love. It’s a good reason why it’s worth keeping the design simple if you’re proposing with a ring. If in doubt, go for a place holder and choose the ring together.
 
SL Man recommends:

EmmaCWebb.com

THFineJewellery.com

W&W Jewellery

To read more about rings, visit JewelleryCut.com.