Assignment 18 - Jade

Question 1

Trade name for finest- quality, semitransparent jadeite with even, vivid green coloration.

Answer 1

Imperial

Question 2

What’s the most desirable jadeite color?

Answer 2

Jadeite’s top color is an even, semitransparent vivid green. This pure, bright color is the renowned Imperial green.

Question 3

How do jadeites texture and transparency affect value?

Answer 3

Jadeite’s transparency ranges from completely opaque to transparent. The best qualities are semitransparent.

Jadeite is an aggregate or rock composed of interlocking mineral grains or crystals. Its texture depends on the size of its interlocking grains: The smaller the grain size, the finer the texture. Fine- grained jadeite usually takes a better polish and has better luster.

Question 4

How do artistry and craftsmanship relate to jadeite value?

Answer 4

Carvers and cutters try to retain as much weight as possible from fine- quality material. The result is that every piece of finished jadeite is unique. This makes artistry and craftsmanship important value factors, especially in the middle to high-end markets.

Question 5

What are some common jadeite treatments?

Answer 5

Impregnation is the most common treatment, as it can improve luster and transparency and make the color appear more saturated.

Dyeing can alter the color of pale or grayish jadeite and more rarely, nephrite.

Asia, the world’s largest jade market, uses Type A (natural), B (chemical), and C (dyed) designations to describe the extent of jade treatment.

Question 6

An uneven distribution of color against a contrasting background.

Answer 6

Mottling

Question 7

Trade term for jadeite with very fine texture.

Answer 7

Old mine

Question 8

Trade term for jadeite with coarse texture.

Answer 8

New mine

Question 9

Gemstone jewelry carved entirely from a single piece of rough.

Answer 9

Hololith

Question 10

What’s the principal source of top-quality jadeite?

Answer 10

Myanmar is a major source, especially of fine-quality material. Other jadeite sources include Guatemala, Russia, Japan, and the US state of California.

Question 11

How is jadeite rough traded?

Answer 11

Once stones are extracted from a mine, they are either auctioned through the official Myanmar Jade, Gems, and Pearl Emporium in the capital city of Nay Pyi Taw or smuggled through different routes to China, the biggest jadeite consumer market.

Question 12

Where and how is jadeite manufactured?

Answer 12

Guangzhou, Jieyang, Sihui, and Pingzhou are the four major jade manufac-turing and trading towns. Each one has its own specialties:
- Jieyang claims the title of “jade capital of Asia” and specializes in medium- to high- quality jadeite products.

• Guangzhou focuses more on trade, due to its privileged geographic location and economic power as a major port and transportation hub.

-Sihui is famous for jadeite carving

• Pingzhou is called the “hometown of jade bangles.”

Question 13

Spots of color near the surface of a jadeite boulder, where the skin is thin enough to allow color to show through.

Answer 13

Show points

Question 14

A polished area on the surface of a jadeite boulder that allows the buyer to see beyond the skin.

Answer 14

Windows

Question 15

What characteristics make nephrite different from jadeite?

Answer 15

Nephrite and jadeite are both extremely tough, but nephrite’s interlocking fibrous structure makes it more resistant to fracturing.

Question 16

What is nephrite’s most sought-after color?

Answer 16

The most sought-after nephrite color is white rather than green.

Question 17

Where are the world’s main nephrite sources and trading centers?

Answer 17

Economically viable nephrite deposits are found around the globe.

The main sources are British Columbia, Canada; Xinjiang Province, China; East Sayan near Russia’s Lake Baikal; and Chuncheon, Korea.

Question 18

What are nephrite’s value factors?

Answer 18

Nephrite quality evaluation is similar to jadeite’s, with many of the same value factors applied by buyers and appraisers. However, there are some differences in interpretation.

One difference is related to the fact that the most sought-after nephrite color is white rather than green.

Since most nephrite is translucent to opaque, transparency is not as critical a value factor as it is for jadeite.

As with jadeite, artistry and craftsmanship are also important to nephrite value. This is especially true for carvings.

Question 19

A trade name for top-quality white nephrite.

Answer 19

Mutton-fat jade

Question 20

Rough nephrite extracted directly from primary deposits.

Answer 20

Mountain jade

Question 21

Rough nephrite recovered from alluvial deposits.

Answer 21

River jade

Question 22

What are some common jade imitations?

Answer 22

Glass and plastic are today’s most common jade imitations.

Question 23

How can buyers spot some jade imitations?

Answer 23

Plastic imitations can easily mimic the colors of both jade types, but its dramatically low specific gravity compared to jadeite and nephrite makes it relatively easy to identify.

By comparison, some glass imitations can be very hard to detect. When they are present, gas bubbles and flow structure can be very helpful for identifying glass imitations.

Question 24

What natural materials are commonly used as jade substitutes?

Answer 24

• Quartzite
• Serpentinite
• Marble
• Green Chalcedony
• Maw-sit-sit
• Hydrogrossular Garnet

Question 25

Polar jade is actually very fine-quality

A. jadeite.

B. nephrite.

C. idocrase.

D. serpentine.

Answer 25

B. nephrite.

High-quality polar jade, named after its source, the Polar Mine in Northern British Columbia, is the trade’s best-known green nephrite.

Question 26

Which country has placed government restrictions on nephrite exports?

Answer 26

New Zealand

Question 27

Where is Maw-Sit-Sit mined?

Answer 27

Near Tawmaw, Myanmar

Question 28

What are the two most common trade names for Hydrogrossular Garnet?

Answer 28

Transvaal jade and African jade.