How to draw a Round Brilliant cut Diamond

Tools you need

  • Paper - Any colour and thickness, suitable for your media. I use Winsor & Newton Extra Smooth Bristol Board Gummed Pad - Bright White

  • Pencil - I use Staedtler 0.3mm Mechanical Pencil

  • Protractor - I use Helix 10cm 360 degrees Protractor Angle Measure

  • Geometry Compass - I use Helix precision drawing set A44002

  • Eraser - I use Eono by Amazon - Battery Operated Automatic Portable Rubber Pencil Eraser

  • Ruler - Any ruler with centimetres will do. Make sure you have a 90-degree triangle

You can find most of the tools I use on Amazon or similar selling platforms


Important before we begin

Diameter: the distance from one side to the other, passing through the centre

Radius: the distance from the centre to any point on the circle

TIP: Try not to push too much with the pencil on the paper as some of the lines will be erased at the end

Lets Begin

Here is going to show if you did well in Geometry at School

Step 1

Always start with finding the centre of your paper, then draw a circle with the compass with the size of the circle you require.

For easier to remember and calculate, let's say the circle is 10cm Diameter (5cm radius - from the centre point to the edge of the circle)

Step 2

After completing the circle, divide it to 16 triangles like so bellow using a Protractor

  1. Separate the circle to 4 sections - 90 Degrees each

  2. Separate it again, now 45 Degrees each

  3. And again, now 22.5 Degrees (In between each 45 Degree triangle)

It loos very complicating but ones you've done it it will get easier for the next time

Step 3

Draw a centre circle 60% smaller than the main one.


If you did a 10cm first circle which is a 5cm radius, the inner circle must be a 6cm diameter or 3cm radius.

Diameter - 60% = Diameter

10cm - 60% = 6cm

7cm - 60% = 2.8cm

5cm - 60% = 2cm

3cm - 60% = 1.2cm

so you have to measure 3cm opening on the compass

Step 4

Draw 2 squares like shown on the picture using the 90 Degree Ruler and just touching the inner circle with the lines.