Starting with the more familiar… sapphire engagement rings are not unusual and as part of the corundum family sapphires are the most durable natural gemstone after diamonds, but did you know they can be found in a whole rainbow of colours, not just the traditional blue.

 You can also find parti-coloured (two different colours in one stone), colour change sapphires that appear different colours under different light sources or even those with a sheen or unusual growth patterns! 

Again, ruby engagement rings are not unusual.  As the red-coloured members of the corundum family they share sapphire’s durability.  If you wanted a very special ruby or sapphire, you could look for a star stone – one with particularly oriented inclusions which make it appear as if a white star is moving backwards and forwards across the surface of the stone as it moves. 

Both rubies and sapphires can really hold their own as a solitaire stone in an engagement ring or why not have a selection of the wide range of colours.

Moving on to the more unusual gemstones, you could consider a spinel engagement ring.  Spinel is an underrated gemstone with great durability which can be found in a variety of colours including pink, red, orange, blue, purple, grey, deep bluish-green, black or even colourless.  Natural, cobalt-blue spinel have recently been appearing on the market – stunning, rare and desirable gemstones, these would make incredible engagement rings!  

Red spinel can make a great alternative to rubies – until the 18th century it wasn’t possible to differentiate between ruby and spinel, so before then, any shiny, transparent red stones found were automatically thought to be rubies.

If you favour green or yellow-green gemstones, you could consider a chrysoberyl engagement ring – they are beautiful stones with great durability.  You can occasionally find pale yellow or green-brown translucent stones which displays a cat’s-eye – a reflected band of light that appears to move as the stone is tilted backwards and forwards, caused by multiple, parallel inclusions.  

For something rare and very unusual you could suggest an alexandrite engagement ring, this colour change variety of chrysoberyl would make a stunning alternative engagement ring as it changes from green in daylight to red in incandescent light.

Even if you are looking for something a little different, don’t discount diamonds altogether –if you don’t fancy a traditional polished colourless diamond, what about a rough diamond engagement ring. 

From the polycrystalline cubes to the unpolished single crystals, these are one of nature’s amazing creations that didn’t require cutting and polishing by man to enhance its beauty. 

If you want to keep a close eye on the budget (and yes, it was another De Beers marketing campaign that tried to dictate how much should be spent on an engagement ring), why not think about manmade diamonds, sapphires or rubies. 

Sometimes described as lab-grown or created, these synthetic gemstones all have identical properties to their natural counterparts and will be as durable and beautiful, but at a lower price point. 

If laboratory grown diamonds are of interest to your customers, please do research behind the marketing to ensure they really do sit in line with your customer’s ethical, environmental or other values as phases such as “mining free” or “ecofriendly” are misleading & incorrect (except for a very few synthetic diamond producers).

What about a colourless stone that’s livelier than a diamond?  Colourless moissanite has been used to imitate diamonds in jewellery since the late 1990s, although the mineral was discovered by Henri Moissan around 100 years earlier in a meteorite strike site in Arizona, USA.

The natural crystals are too small to use in jewellery so all the moissanite seen in jewellery is manmade.  You can also find moissanite with grey, blue, green or yellow tints now, as well as black moissanite. 

These gemstones are cut from large, single crystals of silicon carbide (also known as carborundum, the abrasive used in wet and dry paper!) giving it excellent hardness and all-round great durability.

You may be wondering why I haven’t mentioned emeralds – after all, they have traditionally been considered one of the four “precious” gemstones. I’m afraid it’s down to their durability – they aren’t as hard as the other stones I’ve chosen and are brittle which makes them prone to chipping. 

I have also seen opals, pearls and tanzanite marketed as engagement rings.  Beautiful as all these stones are, they really can’t withstand the daily wear and tear an engagement ring endures – how disappointing would it be to find that a stone in such an important piece of jewellery was damaged beyond repair, or even lost.  A huge thank you to Ella Bullen for letting me use her photo of a damaged tanzanite ring, which demonstrates what can happen...

I’d just like to throw a couple more ideas into the mix… there are some exceptionally exciting and unusual manmade gemstones out there which would be a real talking point…

how about a synthetic sapphire or garnet gemstone, cut from a crystal which was originally grown to be used in lasers…

Once you’ve chosen a gemstone, another important consideration is where you buy it from.  There are many, many reputable gem dealers out there but there are also those who, through misunderstanding, lack of knowledge or sometimes sadly, intent, mis-describe and mis-sell gemstones. 

Perhaps start by looking for someone who is recommended - do extensive research, this is likely to be a considered purchase for customers, so please do take the time to do this. 

Laboratory reports may be offered for higher priced gemstones, which can give some reassurance, but do check for yourself that the laboratory exists, that it is one of their report numbers and that the stone being offered matches the stone detailed on that particular report. 

Lower grade (or even different materials) have been seen which have been cut to match a genuine report – please check & double-check!

Be cautious of plastic, credit card-sized gem certificates – I have found many that are completely misleading about the “stone” they certify while being issued by “laboratories” that don’t even exist… once again, please do your research.