Drawing a diamond may seem intimidating—any design of this gem is extremely complex. The good news is that there is a strong logic behind the arrangement of the diamond’s facets.
Mined rough diamonds are converted into gems through a multi-step process called "cutting". This process is traditionally considered as a delicate procedure that requires skills, special tools, scientific knowledge, and experience. The final goal is to produce a faceted jewel where the specific angles between the facets optimize the dispersion of white light.
A diamond cut is a style or design guide used when shaping a diamond for polishing; this notion refers to the symmetry, proportioning and polish of a diamond.
In this tutorial, we’ll explore and stylize the most popular style—a round cut diamond—in two different foreshortenings.
What You Will Need
You will need the following equipment to complete this project:
- a graphite pencil (I recommend using an HB or H type)
- a pair of compasses
- a protractor
- a ruler
- an eraser
- an ink pen (an optional tool)
- drawing paper
1. How to Draw a Diamond in a Top View
I mark a point; let’s agree that its name will be the point O.
I use it as a central point to draw a circle of an arbitrary radius. A pair of compasses is a great tool for creating an even circumference.
I draw two perpendicular dashed lines going through the central point.
I divide each sector of the circle in half. An easy way to do it is to find the angles of 45°, using the protractor. Now we have eight points of intersection with the circumference.
I also mark the points A and B to make further explanations visually clear.
I connect the points A and B with a dashed line, using a ruler.
I draw a perpendicular line going from the center of the circle to the AB segment, and then extend the line in the opposite direction.
The point D marks the place where this line meets the circumference.
I join the points of intersection with a dashed line to create an octagon.
I divide the sectors of the circle in half once again.
With a ruler, I measure the length of the OB segment, and then find its approximate one-fourth part and mark it with the point C.
Please note that this value may vary—sometimes diamonds of the same design look different. Cutting a diamond is a science, but it's also an art!
With the compasses, I measure the length of the OC segment and add seven more points to other dashed lines, creating new segments of the same length as the OC is.
I connect the points C and D.
I join the point D with the point on the right side to create an angle or a peak.
I repeat connecting the points; now we have a star shape.
I overlay the dashed lines that are located between the star’s peaks with the unbroken strokes.
I mark the point E; it is located at an arbitrary distance from the circle’s center.
Then I measure the length of the OE segment and mark the new points that are equidistant from the center.
I join the points C and E.
I connect more points to create another star-like shape.
I connect the points E and F.
I complete the set of segments that forms a new figure inside the circle.
With an ink pen, I outline the shape of the diamond and erase the subsidiary pencil marks. The drawing is complete!
2. How to Draw a Diamond in a Side View
I draw a straight line, using a ruler. My line’s length is 10 cm—knowing the exact value is beneficial for the next steps because we will be making some measurements.
Please be sure to leave enough space for the lower part of the diamond.
I add another straight line (the distance between the lines is 5 mm) and connect them. Now we have a narrow, elongated rectangle—it’s the draft shape for the diamond’s girdle.
With a protractor, I find the 45° angles and draw two lines. They will intersect at some point and create a basic shape of the diamond's pavilion.
The value of 45° is considered an ideal pavilion angle—it gives the best light performance, but there are many examples that don’t conform to the standard (deep or shallow variants).
It’s time to construct the diamond’s upper part, the crown. I find the angles of 34° (again, this value may be different) and draw two diagonal lines of 2.5 cm each.
I add a straight line to create the table of the diamond.
I draw a dashed line that divides the diamond in half. This will be our reference line to make sure that everything in the drawing is symmetrical.
I create the subsegments inside the OA segment. The first three parts have a length of approximately 1.6 cm, and the fourth part is very short.
I also give the names A, O, and B to the points of the shape to make the demonstrations easier.
Let's agree that the starting point of the first subsegment of the girdle is the point C.
I connect the points B and C.
Then I join the points on the opposite side of the shape, as if I’m mirroring the design.
I divide the CB segment into three approximately equal parts and mark the lower one with the point D.
I connect the points D and O. Then I join the point D with another point on the left side (it's the point E in the illustration below).
I reproduce this set of lines on the opposite side of the shape.
I add the point F; it should be on the same imaginary line as the point D or slightly lower than it. Then I connect the points E and F.
I reproduce this design on the right side of the shape.
Let’s agree that the point marking the shortest part of the girdle is called the point G. I connect the points G and F.
I repeat the same action on the right side of the shape.
I add a short line to the bottom part of the diamond, as if I’m cutting a small part of the shape. Now we have the culet of the diamond (the tiny point at the base).
I divide the OA segment into seven parts and repeat the same action with the symmetrical right half of the diamond.
I draw a distinctive pattern that consists of wider and thinner parts. Actually, there is no strict rule for how a diamond girdle should look, so you can be as creative as you wish.
I complete the girdle.
I draw a vertical dashed line from the point F and mark the point of intersection with the upper line with the letter H.
Then I add another line, going from the corresponding point on the right side; now we get the point H₁.
I divide the side border line of the crown into three parts. The upper segment is marked with the letter I.
I add a corresponding point on the opposite side of the diamond.
I add a line going from the point I to the prominence above the point E.
Then I reflect this line to the opposite side of the drawing.
I add a line going from the point I to the prominence above the point G. Then, as usual, I repeat the pattern on the right side of the shape.
I join the points H and I, and then I mirror the line on the opposite half of the diamond.
I add the point O₁ where the vertical line from the point O intersects the girdle, and a point O₂—where this line meets the top border of the diamond.
I connect the points O₁, H, and H₁.
I draw diagonal lines from the point O₂. The line on the left side is directed to the point E, but we don’t need it and the corresponding line to cross the O₁H and O₁H₁ segments.
In the previous step, we got a small shape that resembles a rhombus; now I mark the side point of this shape with a letter J.
I draw a line that connects the point J with the prominence above the point E.
I repeat the same action on the opposite side of the diamond.
I join the point J with the prominence above the point C, and then add a corresponding line on the right side of the diamond.
I outline the contours of the facets with the ink pen and erase the pencil marks. The diamond is complete!
Your Drawings Are Complete
Congratulations—you did it! I hope that understanding the principles of designing a round cut brilliant diamond will help you to create beautiful diamond artworks or even derivative models of gems.
Anything is simpler if it’s approached with interest and perseverance. I wish you much inspiration; have fun and enjoy the process!