Alexandrite    Amethyst    Aquamarine     Beryl    Chrysoberyl    Citrine     Garnet    Grossular

Iolite
    Mali Garnet    Mandarin Garnet    Moonstone    Morganite    Paraiba tourmaline

Peridot
    Rhodolite    Royal Purpel Garnet    Rubellite    Emerald    Spinel    Tanzanite

Topaz
Tsavorite Tourmaline

Alexandrite

Product information

Stone type Alexandrite
Common types of finishing usually none
Birthstone of the month June
Gemstone group Chrysoberyl
Designation of the best colour in trade
Moh hardness 8,5
Origin Brazil, Madagascar, Sri Lanka, Russia
Processing recommendations*
Ultrasound sensitivity usually none
Reaction to steam usually none
Reaction to heat usually none
Chemical Reaction usually none

 

Amethyst

Stone type Amethyst
Common types of finishing Heating
Birthstone of the month February
Gemstone group Quartz
Designation of the best colour in trade Dark purple/purple
Moh hardness 7
Origin Africa, South America, Russia, USA, India, Canada, Mexico, Zambia, Madagascar, Zambia, Namibia
Processing recommendations*
Ultasound sensitivity Usually none
Reaction to steamRisky
Reaction to heat color change may occur with heat
Chemical reaction Hydrofluoric acid, ammonium fluoride

 

Aquamarine

Stone type Aquamarine
Common types of finishing heating
Birthstone of the month March
Gemstone group Beryl
Designation of the best colour in trade "Santa Maria" or AAA
Moh hardness 7,5-8
Origin Africa, China, Pakistan, Russia, South America, Afghanistan, India

Processing recommendations*

Ultrasound sensitivity usually none
Reaction to steam usually none
Reaction to heat usually none
Chemical reaction Hydrofluoric acid

 

Beryl

Stone type Beryl

Common types of finishing

heating

Birthstone of the month

none

Gemstone group

Beryl

Designation of the best color in trade

dark colour

Moh hardness

7,5-8
Origin world wide

Processing recommendations*

Ultrasound sensitivity usually none
Reaction to steam usually none
Reaction to heat usually none
Chemical reaction Hydrofluoric acid

 

Chrysoberyl

Stone type Chrysoberyl
Common types of finishing heating
Birthstone of the month June
Gemstone group Chrysoberyl
Designation of the best colour in trade neon yellow
Mohshärte 7,5-8
Herkunft Brazil, India, Madagascar, Myamar, Sri Lanka, Tanzania, Simbawe, USA, Russia

Processing recommendations*

Ultrasound sensitivity usually none
Reaction to steam usually none
Reaction to heat usually none
Chemical reaction usually none

 

Citrine

Stone type Citrine
Common types of finishing Heating
Birthstone of the month November
Gemstone Group Quartz
Designation of the best colour in trade golden yellow or orange
Moh hardness 7
Origin Bolivia, Brazil

Processing recommendations*

Ultrasound sensitivity usually none
Reaction to steam risky
Reaction to heat color change may occur with heat
Chemical reaction Hydrofluoric acid,ammonium fluoride

 

Garnet, Mandarin Garnet, Mali Garnet, Royal Purpel Garnet

Stone type Garnet
Common types of finishing usually none
Birthstone of the month January
Gemstone group Garnet
Designation of the best colour in trade ----
Moh hardness 7-7,5
Origin Africa, South America, Asia, Europe

Processing recommendations*

Ultrasound sensitivity usually none
Reaction to steam risky
Reaction to heat usually none
Chemical reaction Hydrofluoric acid

 

Grossular

Stone type Grossular
Common types of finishing usually none
Birthstone of the month none
Gemstone group Garnet
Designation of the best colour in trade intesiv mint
Moh hardness 7-7,5
Origin Kenya, Tanzania, Canada, Mali, Pakistan, Sri Lanka, Russia, South Africa, USA

Processing recommendations*

Ultrasound sensitivity usually none
Reaction to steam risky
Reaction to heat usually none
Chemical reaction Hydroflouric acid

 

Iolite

Stone type Iolite
Common types of finishing usually none
Birthstone of the month none
Gemstone group Iolite
Designation of the best colour in trade medium dark greyish/violet colour
Moh hardness 7-7,5
Origin Brazil, India, Madagascar, Namibia, Sri Lanka, Tanzania
Processing recommendations*
Ultrasound sensitivity risky
Reaction to steam risky
Reaction to heat Poor; Fusible
Chemical reaction Attacked by acids

 

Moonstone

Stone type Moonstone
Common types of finishing usually none
Birthstone of the month June
Gemstone group Feldspar
Designation of the best colour in trade Adularescence
Moh hardness 6-6,5
Origin Australia, Brazil, India, Madagascar, Mexico, Sri Lanka, Tanzania, America

Processing recommendations*

Ultrasound sensitivity Never use
Reaction to steam Never use
Reaction to heat Poor
Chemical reaction Hydrofluoric acid

 

Morganite

Stone type Morganite
Common types of finishing Neutrons, gamma or electrodes irradiated and heated if necessary
Birthstone of the month none
Gemstone group Beryl
Designation of the best colour in trade light-medium pink
Moh hardness 7,5-8
Origin Brazil, Madagascar, America

Processing recommendations*

Ultrasound sensitivity risky
Reaction to steam risky
Reaction to heat Poor-should never be heated
Chemical reaction Hydrofluoric acid and solvents

 

Paraiba Tourmalin

Stone type Paraiba Tourmaline
Common types of finishing heating
Birthstone of the month none
Gemstone group Tourmaline
Designation of the best colour in trade neonblue
Moh hardness 7-7,5
Origin Brazil, Nigeria, Mozambique

Processing recommendations*

Ultrasound sensitivity risky
Reaction to steam usually none
Reaction to heat may cause color change and fracturing
Chemical reaction usually none

 

Peridot

Stone type

Peridot
Common types of finishing usually none

Birthstone of the month

August
Gemstone group Peridot
Designation of the best colour in trade mid-dark yellow/green 

Moh hardness

6,5-7

Origin

Australia, Brazil, China, Kenya, Mexiko, Myanmar, Sri Lanka, America

Processing recommendations*

Ultrasound sensitivity

risky

Reaction to steam

never use

Reaction to heat

heat treatment can cause cracks

Chemical reaction

Sulfuric acid, hydrochloric acid, pickling solution

 

Rhodolite

Stone type

Rhodolite

Common types of finishing

usually none

Birthstone of the month

none

Gemstone group

Garnet

Designation of the best colour in trade

purple

Moh hardness

6,5-7,5
Origin Tanzania, USA, East Africa, India, Madagascar

Processing recommendations*

Ultrasound sensitivity

usually none

Reaction to steam

risky

Reaction to heat

usually none

Chemical reaction

hydrofluoric acid

 

Rubellite

Stone type

Rubellite

Common types of finishing

heating treatment

Birthstone of the month

none

Gemstone group

Turmaline

Designation of the best colour in trade

rasperry red to ruby

Moh hardness

7-7,5

Origin

Nigeria, Mozambique, Brazil

Processing recommendations*

Ultrasound sensitivity

risky

Reaction to steam

risky

Reaction to heat

can cause color change

Chemical reaction

usually none

 

Emerald

Stone type

Emerald 

Common types of finishing

filling cracks with oil, wax or other substances (except glass or plastic) to improve the appearance

Birthstone of the month

none

Gemstone group

Beryl
Designation of the best colour in trade mid-dark green

Moh hardness

7,5-8
Origin Afghanistan, Brazil, Columbia, India, Pakistan, Russia, Samira, Simbabwe

Processing recommendations*

Ultrasound sensitivity

risky

Reaction to steam

never use

Reaction to heat

no heating recommended

Chemical reaction

hydrofluoric acid

 

Spinel

Stone type                        

Spinel

Common types of finishing

usually none

Birthstone of the month

none

Gemstone group

Spinel

Designation of the best colour in trade

pink/red-red or cobaltblue

Moh hardness

8

Origin

Madagascar, Tanzania, Sri Lanka, Afghanistan, Australia, Brazil, Nepal, Nigeria, Tajikistan, Thailand, USA

Processing recommendations*

Ultrasound sensitivity

usually none

Reaction to steam

usually none

Reaction to heat

usually none

Chemical reaction

usually none

 

Tanzanite

Stone type

Tanzanite

Common types of finishing

heat

Birthstone of the month

December

Gemstone group

Zoisit

Designation of the best colour in trade

AAA oder darkblue without lila

Moh hardness

6-7

Origin

Tanzania

Processing recommendations*

Ultrasound sensitivity

never use

Reaction to steam

never use

Reaction to heat

rapid changes in temperature can cause cracks

Chemical reaction

Hydrofluoric& Hydrochloric acid

 

Topaz

Stone type

Topaz

Common types of finishing

Neutron, gamma or electrode irradiation and possibly heating

Birthstone of the month

none

Gemstone group

Topaz

Designation of the best colour in trade

Imperial Topaz (orange/red)

Moh hardness

8
Origin Brasil, Afghanistan, Australia, China, Japan, Mexico, Mozambique,Namibia, Nigeria, Russia, Sri Lanka

Processing recommendations*

Ultrasound sensitivity

never use

Reaction to steam

never use

Reaction to heat

may cause color change

Chemical reaction

usually none

 

Tsavorite

Stone type

Tsavorite

Common types of finishing

usually none

Birthstone of the month

none

Gemstone group

Garnet

Designation of the best colour in trade

green without yellow

Moh hardness

8,5

Origin

Kenia, Tanzania

Processing recommendations*

Ultrasound sensitivity

usually none

Reaction to steam

risky

Reaction to heat

changes in temperature can cause cracks

Chemical reaction

Hydrofluoric acid

 

Tourmaline

Stone type

Tourmaline

Common types of finishing

heating

Birthstone of the month

October

Gemstone group

Tourmaline

Designation of the best colour in trade

----------

Moh hardness

7-7,5

Origin

Sri Lanka, Tanzania, America,Afghanistan, Brazil, China, Eastafrica, Myanmar, Pakistan, India

Processing recommendations*

Ultrasound sensitivity

risky

Reaction to steam

risky

Reaction to heat

can cause color change

Chemical reaction

usually none

 

* The recommendation is non-binding advice. The customer is responsible for the correct processing of the products. The content of the recommendation was written with great care. Nevertheless, no guarantee can be given for the correctness of the recommendations in individual cases.