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Flashcards in Synthetic and Artificial Diamonds Deck (18):
1

What crystal forms are synthetic diamonds form?

Single Crystal and Polycrystalline

2

What is artificial material?

Produced by human manufacturing.

3

Examples of artificial materials:

Glass, concrete, & metal alloys.

4

How are natural materials used for artificial gems?

As feed materials as a core for crystal growth.

5

Synthetic

Artificial materials that possess the same composition and structure as a mineral counterpart. The chemistry, structure, and physical properties must be similar to its natural counterpart.

6

YAG

Yttrium Aluminum Garnet - no natural counterpart

7

What are synthetics used for?

As a substitute or to imitate another species.

8

Synthetic diamond makers:

James B Hannay, Henri Moissan and Sir Charles Parsons

9

What year did synthetic diamonds become reality

1938

10

Allmanna Svenska Elektriska Aktiebolaget (ASEA)

1953 Swedish engineering company grew 40 synthetic crystals.

11

Synthetic diamond are grown by HPHT

Belt or BAR methods

12

Synthetic Diamond Formula

Carbon Source, 50-80 kb pressure, 1350-1600 Celsius, and metal solvent catalyst (iron, nickel, cobalt, and alloys of these metals).

13

How does the synthesis takes place?

The carbon material is absorbed into the surrounding metal solvent until it reaches saturation point and crystallizes as a diamond.

14

What carbon source is best for gem quality synthetics?

Diamond powder

15

What's the problem with using graphite as a carbon source?

Loss of volume when broken bonds between atoms reform as diamond, causing loss in pressure.

16

What carbon source is used?

Diamond powder and graphite.

17

Synthetic is affected by:

Temperature and pressure

18

Most predominant synthetic shape

Cubo-octahedron