When a partner pops the question, a girl dreams that it will be a most romantic moment. Luckily, I had just such a proposal. My husband asked me to marry him half way across Waterloo Bridge – my favourite view in London – and presented me with a beautiful diamond sparkler. I could not have planned it better myself.

He chose the ring, a simple yet stunning solitaire. I wasted no time showing it off to my friends and family. However, a year later the delight faded when the diamond fell out. I thought diamonds were meant to last forever. Obviously not this one.

It was a mystery how it happened. I didn’t catch the stone on anything; it wasn’t forced out with pliers or bitten off by a small child like my sister-in-law’s. It just went missing and I felt terrible. We were only a few months away from the big day and I couldn’t face the thought of getting married without it.

After a lengthy wrangle with the jewellers they finally agreed to replace the ring, but I can’t help wondering if I might have been spared all the worry and trouble if the ring had been made of platinum.

This rare metal not only has a lustrous look and feel, it has substance – it is the perfect metal to hold a diamond securely in its setting. Platinum is more durable than other jewellery metals and because it does not wear away you can be sure your wife will be able to wear her engagement ring on your silver, gold, or even platinum wedding anniversary.

For this once in a lifetime purchase, you want the metal to be the best. Naturally white, platinum is 95 per cent pure - check for the Pt 950 mark. According to the UK manager of the Platinum Guild, Ruth Donaldson, it does not tarnish and so keeps its looks for a lifetime. The luminous-white colour also reflects the radiance of diamonds brilliantly for that extra bit of sparkle.

A precious metal, it is 30 times rarer than gold. Actually, it is estimated that if all the platinum in the world was poured into an Olympic size swimming pool it would only cover a person’s ankles, while gold would fill more than three pools. So let the world see how much you value her, when you buy her a platinum ring.

Following my experience, I’d suggest to any chap planning to pop the question to really do their homework before buying what is, a once in a lifetime purchase. The Precious Platinum website contains knowledgeable advice on platinum jewellery as well as information and inspiration on what to buy.

There is no better time than Christmas to get down on one knee, with mistletoe dangling from many doorways everyone is in the mood for romance. So, why wait? Surprise her with a proposal and a platinum engagement ring – the perfect Christmas gift and one that she will treasure for a lifetime.