Welcome to our diamond guide, here we will give you the basic knowledge needed to make an informed decision on the diamond grade that's right for you.

Lloyds Family Jewellery only trade in 100% natural, none treated and conflict free diamonds.

What are the most popular diamond grades you offer?

What is a Diamond?

View how a diamond is graded by GIA.

Diamond Cut Explained.

Diamond Colour Explained.

Diamond Clarity Explained.

Diamond Carat Weight (cts) Explained.

Diamond Measurements: Approximate Carat to Size Ratio.

At Lloyds Family Jewellery we offer 3 Diamond grades readily available. You may want to read up about the 4 C's on this page to get a better understanding of the grades below.

Grade 1. Colour: Near Colourless H-J, Clarity: Included I1

(provided in items that do not specify a particular grade)

These diamonds are a standard grade giving you more diamonds for your money, higher grade diamonds as discussed below are more valuable. These diamonds are near colourless with no easily noticeable colour tint to the untrained eye. Inclusions in the diamond may be noticeable if you look closely at the stone. Inclusions have an effect on brilliance although these diamonds still give a nice amount of sparkle. This grade is generally provided with 9k gold items.

Grade 2. H/SI (H Colour/Slightly Included)

This means the diamonds are no less than H grade colour (near colourless) as you can see on the scale below, and SI clarity meaning slightly included which you can also see below. These diamonds are a higher grade meaning they give more sparkle with a whiter looking colour, they are also more valuable due to the rarity of higher grade diamonds.

Grade 3. G/VS (G Colour/Very Slightly Included)

An exceptional grade, this means the diamond is no less than G colour and VS clarity which means Very Slightly included (you will see a more detailed description of what inclusions are below). These diamonds are classed as colourless with only slight inclusions meaning they give a beautiful amount of brilliance (sparkle), they are also much more valuable than lower grade diamonds due to the rarity of these high grade diamonds.

Many of our items are available in a choice of diamond grades, our engagement ring collection can be supplied with any desired diamond grade as a special order.

Please contact us for further details

What Is A Diamond?

Diamonds are a rare composition of pure crystallized carbon, formed under extremely high heat and pressure deep within the earth. They are aged between 1 and 3.3 billion years old (up to 75% of the earths age) and are brought close to the surface by volcanic eruptions. Most Diamonds contain impurities, not defects but better to think of these as birthmarks which makes each diamond unique, most impurities can not be seen with the naked eye. Diamonds are the hardest natural substance on earth, the name diamond comes from the ancient Greek Adámas meaning "unbreakable". Due to their incredible optical properties and hardness, diamonds are the most prized of all gemstones.

The Four C's: Cut, Colour, Clarity, Carat Weight

The best way of grading a diamond is by using the four C's as shown below, then combining these to give the grade and to help calculate the value. Diamond pricing is a complicated process and takes many other factors into account as well as the four C's. The four C's were established by the Gemological Institute of America (GIA) and has since become the international standard for diamond grading.

View the video below for a quick master class from the experts at GIA. See the steps taken to grade a diamond in the diamond grading process.

 Staff at Lloyds Family Jewellery are trained by GIA and are certified with the Diamond Essentials certificate.

Diamond Cut:

Cut has a big impact on the beauty of diamonds,The word cut has several meanings when it comes to diamonds. The cut of a diamond does not just mean its shape (round brilliant, princess, oval, cushion, etc.) but also addresses the symmetry, dimensions and proportions of a diamond.

The cut determines the diamond's brilliance (white flashes) and fire (light split into all colours in the spectrum, red, green etc). A properly cut diamond will reflect the light that enters the diamond and return it through the table to produce the much desired sparkle. The angles should be within the correct parameters to optimize the reflection of light back to the eye. The cut, as well as symmetry and polish can also be graded. 

Diamonds can be cut in various shapes including;

Diamond Colour:

Diamonds are not only colourless as many people think, most diamonds have tones of faint yellow or brown, the higher a diamond is towards the top of the colour scale, the rarer the diamond becomes and so more valuable. Diamonds can also be found in a variety of colours and hues such as Pink, Red, Blue and Green, these are known as fancy colours and are graded separately from the usual colour scale. Fancy diamonds are much rarer than the more common and sought after colourless diamonds. With 'white' diamonds the less colour the more valuable the diamond becomes, faint signs of yellow or brown can decrease value. Colours are graded in letters from D meaning colourless all the way to Z meaning light yellow or brown. The scale does not include the letters A, B or C, as to not confuse the scale with older, less accurate methods of grading.

Diamond Clarity:

This indicates how clear the diamond from inclusions. This plays a big part in determining value, Inclusions may be; dark carbon spots, white crystal particles (which can cluster together to make 'clouds') and internal or external fractures. Man made defects by the cutter can also be taken into account such as polish lines or extra facets which may have been placed there to remove an inclusion. Diamonds can also be damaged, remember diamonds are extremely hard but will chip or fracture if struck hard enough. The grades for Clarity are shown below.

Common Grades: 

• F: Flawless
• IF: Internally Flawless
• VVS: Very Very Slightly Included
• VS: Very Slightly Included
• SI: Slightly included
• I1: Included 1
• I2: Included 2
• I3: Included 3
  

The number 1 or 2 can also be added; this represents the extent of inclusions, 1 being the cleanest. Number 3 is reserved for I grade diamonds, this represents a diamond with lots of inclusions which would be more noticeable to the naked eye.

Diamond Carat Weight:

Most people think of this as being the diamonds size, when in fact it is the weight.

When looking at a single diamond; the heavier the carat weight, the rarer the diamond becomes and therefor more valuable (assuming all other grading criteria are equal). Carat/s is usually abbreviated to ct or cts. One carat equals 1/5th of a gram, in other words... there are 5 carats in 1 gram. You may also have heard a diamond referred to in points. There are 100 points in a 1.00ct diamond, therefore a quarter carat or 0.25ct diamond has 25 points.

Carat weight may also refer to the total weight of diamonds in a piece of jewellery. A diamond ring may consist of 10x 0.10ct diamonds or 100x 0.01ct diamonds and both would have a carat weight of 1.00ct (one carat) however the item with 10 diamonds would generally be more expensive, this is due to the fact that 10 larger diamonds are rarer than the equivelant weight of 100 tiny diamonds which makes them more valuable.

Here's where is can get complicated. During the diamond cutting process the cutter wants to get the heaviest diamond out of a rough stone, however this can come at the cost of lowering the cut grade. If a diamond is too deep, this will increase carat weight but results in a loss of brilliance due to light leakage. Diamond cutters have to compromise between finishing with the heaviest weight possible while still keeping good proportions. This is why you can have two diamonds of the same weight but one can be bigger than the other. A well cut 0.90ct diamond could have the same width as a poorly cut 1.00ct diamond (this is known as spread). These two diamonds however could be of equal value, which would you go for? Heavier weight or a higher cut grade.

Some common Diamond weights;

• 0.25ct (quarter carat)
• 0.50ct (half carat)
• 0.75ct (three quarter carat)
• 1.00ct (1 carat)

Most diamonds sold in jewellery are under 1.00ct although diamonds can reach incredible sizes; the largest ever rough gem quality diamond was the cullinan diamond found at the Premier Mine, South Africa. This incredible diamond weighed 3,106.75cts, the diamond was split to create nine pieces, the largest piece is a pear cut diamond weighing 530.4cts and named the Great Star of Africa. It now resides in the Crown Jewels of England in the Royal Sceptre.

The word "carat" comes from the ancient practice in India where diamonds were first thought to have been discovered and traded, they measuring diamond weights with the one thing in nature that is both small and the most consistent in weight -- the carob seed. Thus the name "carat" evolved in the English language, which is still equivalent to approximately the weight of one carob seed. Carat weights are very precise, they are weighed to a thousandth of a carat then rounded off to the nearest hundred.

For diamond sizes see the chart below, please note these sizes are a guide only. Actual diamonds may differ depending on proportions. 

	Round Cut
Millimeters	Carat weight	Points
1.0	0.005	0.5
1.3	0.01	1
1.5	0.015	1.5
1.7	0.02	2
1.8	0.025	2.5
2.0	0.03	3
2.1	0.035	3.5
2.2	0.04	4
2.4	0.05	5
2.5	0.06	6
2.7	0.07	7
2.8	0.08	8
2.9	0.09	9
3.0	0.10	10
3.1	0.11	11
3.2	0.12	12
3.3	0.14	14
3.4	0.15	15
3.5	0.16	16
3.6	0.17	17
3.7	0.18	18
3.8	0.20	20
3.9	0.22	22
4.0	0.25	25
4.2	0.30	30
4.4	0.33	33
4.5	0.35	35
4.6	0.38	38
4.8	0.40	40
5.0	0.50	50
5.4	0.60	60
5.5	0.63	63
5.6	0.65	65
6.0	0.75	75
6.4	0.95	95
6.6	1.00	100
6.8	1.17	117
7.0	1.25	125
7.2	1.33	133
7.5	1.55	155
7.8	1.75	175
8.0	2.00	200
8.4	2.15	215
8.6	2.25	225
9.0	2.75	275
9.4	3.00	300
9.6	3.15	315
9.8	3.35	335
10.0	3.50	350
10.2	3.75	375
10.4	4.00	400
10.6	4.25	425
10.8	4.50	450
11.0	4.75	475
11.2	5.00	500
12.0	6.50	650

	Oval Cut
Millimeters	Carat weight	Points
4 x 3	0.20	20
5 x 3	0.25	25
5 x 3.5	0.33	33
5 x 4	0.40	40
6 x 4	0.50	50
6.5 x 4.5	0.65	65
7 x 5	0.75	75
7.5 x 5.5	1.00	100
8 x 6	1.25	125
8.5 x 6.5	1.50	150
9 x 6	1.75	175
9 x 7	2.00	200
9.5 x 7.5	2.50	250
10 x 8	3.00	300
10 x 8.5	3.50	350
11 x 9	4.00	400
11 x 9.5	4.50	450
12 x 10	5.00	500

	Marquise Cut
Millimeters	Carat weight	Points
3.5 x 1.5	0.07	7
4 x 2	0.10	10
5 x 2	0.20	20
5 x 3	0.22	22
5.5 x 2.5	0.25	25
6 x 6	0.30	30
7 x 3	0.35	35
7 x 3.5	0.38	38
7 x 4	0.40	40
8 x 4	0.50	50
8.5 x 4.5	0.65	65
9 x 4	0.70	70
9 x 4.5	0.75	75
9 x 5	0.80	80
9.5 x 4.5	0.85	85
10 x 4.75	1.00	100
10 x 5	1.25	125
11 x 5	1.50	150
11 x 5.5	1.65	165
12 x 6	2.00	200
13 x 5.5	2.50	250
13 x 6	2.65	265
14 x 6.5	2.87	287
14 x 7	3.00	300
15 x 7	3.75	375
16 x 8	4.50	450
18 x 9	7.00	700
20 x 10	10.00	1000

	Princess Cut
Millimeters	Carat weight	Points
2.00	0.06	6
2.25	0.08	8
2.50	0.10	10
2.75	0.13	13
3.0	0.15	15
3.25	0.20	20
3.5	0.23	23
3.75	0.25	25
4.0	0.30	30
4.42	0.35	35
4.5	0.40	40
4.75	0.50	50
5.0	0.63	63
5.25	0.75	75
5.5	1.00	100
6.0	1.25	125
7.0	1.60	160
8.0	2.25	225

	Emerald Cut
Millimeters	Carat weight	Points
4 x 3	0.20	20
5 x 3	0.25	25
6 x4	0.50	50
6.5 x 4.5	0.75	75
7 x 5	1.00	100
8 x 6	1.50	150
8.5 x 6.5	2.00	200
9 x 7	2.50	250
10 x 8	3.00	300
11 x 9	4.00	400
12 x 10	5.00	500

	Pear Cut
Millimeters	Carat weight	Points
4 x 2	0.20	20
5 x 3	0.30	30
6 x 4	0.50	50
7 x 5	0.75	75
8 x 5	1.00	100
9 x 6	1.50	150
10 x 7	2.00	200
12 x 7	2.50	250
12 x 8	3.00	300
13 x 8	3.50	350
14 x 8	4.00	400
15 x 9	5.00	500

If you have any other questions or think we have missed something that should be included in this guide please let us know by contacting us>