Assignment 8 - Diamond Cutting

Question 1

When did diamonds first appear in Jewelery?

Answer 1

100 AD, diamonds were set into jewellery by the Romans. Around 1200 AD they began to appear in royal European jewellery.

Question 2

How did improvements of tools advance diamond cutting?

Answer 2

Before the 15th century, diamond “cutting” was limited to superficial polishing of the rough.

In the 16th century, developments of continuous rotary motion and the cast-iron polishing wheel shifted diamond cutting from superficial polishing to genuine faceting.

Question 3

The process of dividing rough diamond along its cleavage planes

Answer 3

Cleaving

Question 4

The process by which a rough diamond is shaped into its basic face-up outline to prepare for faceting

Answer 4

Bruting

Question 5

The process of dividing a rough diamond into different sections using a saw.

Answer 5

Sawing

Question 6

What are some important events in the history of diamond cutting?

Answer 6

• Invention of the bruting machine and the motorized diamond saw made mass production possible
• Rough mapping, computerized planning, and laser processing made diamond cutting more efficient and more profitable.

Question 7

When and where did the first cut diamonds appear?

Answer 7

The first polished diamonds appeared in Europe around 1380.

Question 8

A diamond cut with a flat bottom and triangular facets that come to a point at the top

Answer 8

Rose cut

Question 9

What were the earliest diamond cuts?

Answer 9

• Point Cut (1300-1500)
• Table Cut (1400-1600)
• Rose Cut (1500-1800)

The cuts followed the shape of the octahedral rough.

Question 10

How did the brilliant cut develop?

Answer 10

• Single Cut (1650)
• Old-Mine Cut (1700)
• Old European Cut (1750)
• Modern Brilliant Cut (1900)

Question 11

What are some of the newer diamond cuts?

Answer 11

• Round Brilliant
• Princess Cut (Rectangular/Square)
• Triangular Brilliant
• Marquise Cut
• Pear Cut

Question 12

A simple diamond cut, with a table, eight crown facets and sometimes a culet.

Answer 12

Single Cut

Question 13

An early cushion-shaped brilliant with a high crown, deep pavilion, and 58 facets including a large culet.

Answer 13

Old-mine Cut

Question 14

An early brilliant cut with a circular girdle.

Answer 14

Old European Cut.

Question 15

What is a cutter’s main challenge?

Answer 15

The cutter’s challenge is to produce the most attractive and most profitable gem at the lowest production costs.

Question 16

Why is the planning stage so crucial?

Answer 16

Planning has a massive impact on the profitability of the finished stones.

Question 17

What are the main steps in the cutting process?

Answer 17

• Planning
• Cleaving / Sawing
• Bruting (& Coning)
• Polishing (Blocking & Brillianteering)

Question 18

Dividing a diamond into two or more pieces along a cleavage plane

Answer 18

Cleaving

Question 19

Dividing diamond rough into sections, either mechanically or by laser

Answer 19

Sawing

Question 20

The person who decides where to mark diamond rough for fashioning into the most profitable polished gem

Answer 20

Planner

Question 21

A notch scratched into a diamond rough to prepare it for cleaving

Answer 21

Kerf

Question 22

A holder that secures a diamond during sawing, bruting, or polishing

Answer 22

Dop

Question 23

Forming the basic face-up outline of a round or rounded-shape diamond to prepare it for faceting

Answer 23

Bruting

Question 24

Placing and finishing facets on a rough diamond

Answer 24

Polishing

Question 25

The process of forming the pavilion angle by gradually polishing off the extra material at different angles.

Answer 25

Coning

Question 26

A rapidly spinning horizontal disc coated with diamond powder, used to polish diamond rough

Answer 26

Scaife

Question 27

A device that holds the dop and allows polishers to adjust and maintain a diamond’s angle during polishing

Answer 27

Tang

Question 28

Placing the first 17 to 18 facets on a diamond

Answer 28

Blocking

Question 29

Placement and polishing of the star and upper and lower half facets

Answer 29

Brillianteering

Question 30

What cut style results from blocking?

Answer 30

Single Cut

Question 31

Why did cutters first make a table cut?

Answer 31

To avoid chipping

Question 32

What outline shape was most common to early brilliant cuts?

Answer 32

Before the invention of the bruting machine, the cushion shape was the easiest to cut, because it follows the natural outline of octahedral diamond crystals.

Question 33

Why did cutters apply the modern brilliant cut to fancy shapes?

Answer 33

To maximize profits from oddly shaped or off-color rough.

Question 34

How does laser sawing increase weight retention?

Answer 34

Because the beam is thinner than with traditional saws.

Question 35

What early cut introduced the culet?

Answer 35

Table cut.