Slightly Included Diamonds

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SI - Sligtly Included

SI means sligthly included. SI diamonds have inclusions that are easily noticeable by an experienced grader with a 10x loupe. How easy it is to spot would depend on the SI grade as follows:

SI1: Easy
SI2: Very Easy
SI3: Obvious

SI clarity grades are a lot cheaper, simply because at this clarity grade, there is a danger that people will be able to spot the inclusions with the naked eye.

However, not all SI diamonds are created equal. You may be able to find SI diamonds that are completely eye-clean, when it is mounted in a setting. But, it is highly likely that you will be able to see the inclusions from the side, or from the pavilion.

Personally, I do not think that you should consider an SI diamond if you intend to use it for your proposal. It is likely that if she knows where the inclusions are from the certificate, and she keeps an eye out for them, they will be spotted. As she stares at them over the years, they will appear bigger.

When I say eye-clean, it means it looks like it is free from inclusions to a casual observer, from a distance of about 50cm. Well cut SI diamonds are therefore great value if you are using them for regular jewellery.

Below is an example of how an SI diamond would look:

1.542ct H SI2