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About Dysprosium

Dysprosium Bohr

French chemist Paul Emile Lecoq de Boisbaudran isolated dysprosium oxide from an impure sample of holmium oxide in 1886. He had great difficulty deriving the metal itself from the oxide, and thus named the element from the Greek dysprositos, meaning “hard to get”. It is unsurprising that the metal was so hard to isolate, as significant pure quantities of many of the rare earth elements could not be obtained until ion exchange techniques were developed in the 1950s.

A number of compounds containing dysprosium emit light under defined conditions, making them useful for a number of applications. Dysprosium-doped calcium sulfate or calcium fluoride crystals luminesce when they have been exposed to radiation, and thus are used in dosimeters for measuring radiation exposure. Dysprosium iodide and bromide are used in metal-halide lamps, which produce extremely bright white light that is valued in the film industry. Additionally, dysprosium compounds can be used to produce infrared light and are often used in infrared lasers.

Dysprosium and its compounds are also valued for their magnetic properties. Easily magnetized dysprosium compounds can be used in data storage applications such as hard drives, and dysprosium is often used to substitute for some of the neodymium in neodymium-iron-boron magnets. Substituting these high-powered magnets with dysprosium increases their corrosion resistance and coercivity. Neodymium magnets are essential for electric motors, magnetic memory devices such as hard drives, and many other modern electronics. Dysprosium-containing garnets with magnetic properties are used in magnetic refrigeration devices, which can be used to reach extremely low temperatures. Finally, Terfenol-D is an alloy of terbium, iron, and dysprosium that is magnetostrictive: it contracts or expands when exposed to magnetic fields. This property allows direct conversion between electrical and mechanical power, and the alloy is used in sensors, actuators, and acoustic and ultrasonic transducers, and active noise and vibration cancelling devices.

Dysprosium is highly effective at absorbing neutrons, and is therefore used in nuclear reactor control rods. It can also be used to produce nanofibers that have high strength and are naturally corrosion resistant, and these have the potential for use as reinforcement in ceramic materials designed for high-temperature applications.

Dysprosium, like other rare earth elements, is never found in its pure form in nature. It can be obtained only from rare earth containing minerals such as xenotime, monazite, and bastnasite, or from ion-adsorption clays.


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Dysprosium is most commonly used in neodymium-iron-boron high strength permanent magnets. While it has one of the highest magnetic moments of any of the rare earths (10.6µB), this has not resulted in an ability to perform on its own as a practical alternative to neodymium compositions. It is however now an essential additive in NdFeB production. Dysprosium is also used in special ceramic compositions based on BaTiO formulations. Recent research has examined the use of dysprosium in dysprosium-iron-garnet (DyIG) and silicon implanted with dysprosium and holmium to form donor centers. Dysprosium is added to various advanced optical formulations due to the fact that it emits in the 470-500 and 570-600 nm wavelengths. High Purity (99.995%) Dysprosium (Dy) Sputtering Target Dysprosium metal is used in rare earth magnet alloys and magnesium alloys.High Purity (99.999%) Dysprosium Oxide (Dy2O3) Powder Due to dysprosium's high susceptibility to magnetization, it is also used in a variety of data storage applications, such as in compact discs. Dysprosium is available as metal and compounds with purities from 99% to 99.999% (ACS grade to ultra-high purity). Elemental or metallic forms include pellets, rod, wire and granules for evaporation source material purposes. Dysprosium oxide is available in powder and dense pellet form for such uses as optical coating and thin film applications. Oxides tend to be insoluble. Dysprosium fluorides is another insoluble form for uses in which oxygen is undesirable such as metallurgy, chemical and physical vapor deposition and in some optical coatings. Dysprosium is also available in soluble forms including chlorides, nitrates and acetates. These compounds can be manufactured as solutions at specified stoichiometries.

Dysprosium Properties

Dysprosium Element SymbolDysprosium is a Block F, Group 3, Period 6 element. Dysprosium Bohr Modelelemental form, CAS 7429-91-6, dysprosium has a silvery-white appearance. Dysprosium is found in various minerals including bastnäsite, blomstrandine, euxenite, fergusonite, gadolinite, monazite, polycrase and xenotime. It is not found in nature as a free element. Monazite sand is the primary commercial source of dysprosium. Dysprosium was first discovered by Paul Emile Lecoq de Boisbaudran in 1886. The element name originates from the Greek word 'dysprositos' meaning hard to get at.

Symbol: Dy
Atomic Number: 66
Atomic Weight: 162.5
Element Category: Lanthanide
Group, Period, Block: n/a, 6, f
Color: silvery-white
Other Names: Disprosio
Melting Point: 1412 °C, 2573.6 °F, 1685.15 K
Boiling Point: 2567 °C, 4652.6 °F, 2840.15 K
Density: 8.550 g/cm3
Liquid Density @ Melting Point: 8.37 g·cm3
Density @ 20°C: 8.536 g/cm3
Density of Solid: 8551 kg·m3
Specific Heat: 0.0414 Cal/g/K @ 25°C
Superconductivity Temperature: N/A
Triple Point: N/A
Critical Point: N/A
Heat of Fusion (kJ·mol-1): 17.2
Heat of Vaporization (kJ·mol-1): 293
Heat of Atomization (kJ·mol-1): 293.05
Thermal Conductivity: 0.107 W/cm/K @ 298.2 K
Thermal Expansion: (r.t.) (?, poly) 9.9 µm/(m·K)
Electrical Resistivity: 57.0 µΩ-cm @ 25°C
Tensile Strength: N/A
Molar Heat Capacity: 27.7 J·mol-1·K-1
Young's Modulus: (? form) 61.4 GPa
Shear Modulus: (? form) 24.7 GPa
Bulk Modulus: (? form) 40.5 GPa
Poisson Ratio: (? form) 0.247
Mohs Hardness: N/A
Vickers Hardness: 540 MPa
Brinell Hardness: 500 MPa
Speed of Sound: (20 °C) 2710 m·s-1
Pauling Electronegativity: 1.22
Sanderson Electronegativity: N/A
Allred Rochow Electronegativity: 1.1
Mulliken-Jaffe Electronegativity: N/A
Allen Electronegativity: N/A
Pauling Electropositivity: 2.78
Reflectivity (%): N/A
Refractive Index: N/A
Electrons: 66
Protons: 66
Neutrons: 96
Electron Configuration: [Xe] 4f10 6s2
Atomic Radius: 178 pm
Atomic Radius,
non-bonded (Å):
Covalent Radius: 192±7 pm
Covalent Radius (Å): 1.8
Van der Waals Radius: 229 pm
Oxidation States: 3, 2, 1 (weakly basic oxide)
Phase: Solid
Crystal Structure: hexagonal close-packed
Magnetic Ordering: paramagnetic
Electron Affinity (kJ·mol-1) Unknown
1st Ionization Energy: 573.02 kJ·mol-1
2nd Ionization Energy: 1125.99 kJ·mol-1
3rd Ionization Energy: 2199.88 kJ·mol-1
CAS Number: 7429-91-6
EC Number: 231-073-9
MDL Number: MFCD00010982
Beilstein Number: N/A
SMILES Identifier: [Dy]
InChI Identifier: InChI=1S/Dy
PubChem CID: 23912
ChemSpider ID: 22355
Earth - Total: 364 ppb
Mercury - Total: 280 ppb
Venus - Total: 382 ppb
Earth - Seawater (Oceans), ppb by weight: 0.00091
Earth - Seawater (Oceans), ppb by atoms: 0.000035
Earth -  Crust (Crustal Rocks), ppb by weight: 6200
Earth -  Crust (Crustal Rocks), ppb by atoms: 790
Sun - Total, ppb by weight: 2
Sun - Total, ppb by atoms: 0.01
Stream, ppb by weight: 0.05
Stream, ppb by atoms: 0.0003
Meterorite (Carbonaceous), ppb by weight: 280
Meterorite (Carbonaceous), ppb by atoms: 30
Typical Human Body, ppb by weight: N/A
Typical Human Body, ppb by atom: N/A
Universe, ppb by weight: 2
Universe, ppb by atom: 0.02
Discovered By: Lecoq de Boisbaudran
Discovery Date: 1886
First Isolation: N/A

Health, Safety & Transportation Information for Dysprosium

Dysprosium is moderately toxic. Safety data for Dysprosium and its compounds can vary widely depending on the form. For potential hazard information, toxicity, and road, sea and air transportation limitations, such as DOT Hazard Class, DOT Number, EU Number, NFPA Health rating and RTECS Class, please see the specific material or compound referenced in the Products tab. The below information applies to elemental (metallic) Dysprosium.

Safety Data
Signal Word Warning
Hazard Statements H228
Hazard Codes F
Risk Codes 11
Safety Precautions 22-24/25
RTECS Number N/A
Transport Information N/A
WGK Germany 3
Globally Harmonized System of
Classification and Labelling (GHS)
Review and Print SDS for Dysprosium Metal


Date Created: 05/15/2015
Date Revised: 05/15/2015


Product Name: Dysprosium Metal

Product Number: All applicable American Elements product codes, e.g. DY-M-02, DY-M-03, DY-M-035, DY-M-04, DY-M-05

CAS #: 7429-91-6

Relevant identified uses of the substance: Scientific research and development

Supplier details:
American Elements
1093 Broxton Ave. Suite 2000
Los Angeles, CA 90024
Tel: +1 310-208-0551
Fax: +1 310-208-0351

Emergency telephone number:
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International +1 703-527-3887


Classification of the substance or mixture in accordance with 29 CFR 1910 (OSHA HCS)
The substance is not classified according to the Globally Harmonized System (GHS).
Hazards not otherwise classified
No information known.
Label elements
GHS label elements
Not applicable
Hazard pictograms
Not applicable
Signal word
Not applicable
Hazard statements
Not applicable
WHMIS classification
Not controlled
Classification system
HMIS ratings (scale 0-4)
(Hazardous Materials Identification System)
Health (acute effects) = 1
Flammability = 1
Physical Hazard = 1
Other hazards
Results of PBT and vPvB assessment
Not applicable.
Not applicable.


Chemical characterization: Substances
CAS# Description:
7429-91-6 Dysprosium
Identification number(s):
EC number:


Description of first aid measures
After inhalation
Supply fresh air. If required, provide artificial respiration. Keep patient warm.
Seek immediate medical advice.
After skin contact
Immediately wash with water and soap and rinse thoroughly.
Seek immediate medical advice.
After eye contact
Rinse opened eye for several minutes under running water. Then consult a doctor.
After swallowing
Seek medical treatment.
Information for doctor
Most important symptoms and effects, both acute and delayed
No further relevant information available.
Indication of any immediate medical attention and special treatment needed
No further relevant information available.


Extinguishing media
Suitable extinguishing agents
Special powder for metal fires. Do not use water.
For safety reasons unsuitable extinguishing agents
Special hazards arising from the substance or mixture
If this product is involved in a fire, the following can be released:
Metal oxide fume
Advice for firefighters
Protective equipment:
Wear self-contained respirator.
Wear fully protective impervious suit.


Personal precautions, protective equipment and emergency procedures
Wear protective equipment. Keep unprotected persons away.
Ensure adequate ventilation
Environmental precautions:
Do not allow material to be released to the environment without proper governmental permits.
Methods and material for containment and cleaning up:
Pick up mechanically.
Prevention of secondary hazards:
No special measures required.
Reference to other sections
See Section 7 for information on safe handling
See Section 8 for information on personal protection equipment.
See Section 13 for disposal information.


Precautions for safe handling
Keep container tightly sealed.
Store in cool, dry place in tightly closed containers.
Information about protection against explosions and fires:
No information known.
Conditions for safe storage, including any incompatibilities
Requirements to be met by storerooms and receptacles:
No special requirements.
Information about storage in one common storage facility:
Do not store together with acids.
Store away from acid chlorides.
Store away from halogens.
Further information about storage conditions:
Keep container tightly sealed.
Store in cool, dry conditions in well sealed containers.
Specific end use(s)
No further relevant information available.


Additional information about design of technical systems:
Properly operating chemical fume hood designed for hazardous chemicals and having an average face velocity of at least 100 feet per minute.
Control parameters
Components with limit values that require monitoring at the workplace:
The product does not contain any relevant quantities of materials with critical values that have to be monitored at the workplace.
Additional information:
No data
Exposure controls
Personal protective equipment
General protective and hygienic measures
The usual precautionary measures for handling chemicals should be followed.
Keep away from foodstuffs, beverages and feed.
Remove all soiled and contaminated clothing immediately.
Wash hands before breaks and at the end of work.
Maintain an ergonomically appropriate working environment.
Breathing equipment:
Use suitable respirator when high concentrations are present.
Protection of hands:
Impervious gloves
Check protective gloves prior to each use for their proper condition.
The selection of suitable gloves not only depends on the material, but also on quality. Quality will vary from manufacturer to manufacturer.
Penetration time of glove material (in minutes)
Not determined
Eye protection:
Safety glasses
Body protection:
Protective work clothing


Information on basic physical and chemical properties
General Information
Form: Solid in various forms
Color: Grey to silver
Odor: Odorless
Odor threshold: Not determined.
pH-value: Not applicable.
Change in condition
Melting point/Melting range: 1412 °C (2574 °F)
Boiling point/Boiling range: 2567 °C (4653 °F)
Sublimation temperature / start: Not determined
Flammability (solid, gaseous)
Not determined.
Ignition temperature: Not determined
Decomposition temperature: Not determined
Auto igniting: Not determined.
Danger of explosion: Not determined.
Explosion limits:
Lower: Not determined
Upper: Not determined
Vapor pressure: Not applicable.
Density at 20 °C (68 °F): 8.55 g/cm³ (71.35 lbs/gal)
Relative density
Not determined.
Vapor density
Not applicable.
Evaporation rate
Not applicable.
Solubility in / Miscibility with Water: Insoluble
Partition coefficient (n-octanol/water): Not determined.
dynamic: Not applicable.
kinematic: Not applicable.
Other information
No further relevant information available.


No information known.
Chemical stability
Stable under recommended storage conditions.
Thermal decomposition / conditions to be avoided:
Decomposition will not occur if used and stored according to specifications.
Possibility of hazardous reactions
Spontaneously flammable in air.
Conditions to avoid
No further relevant information available.
Incompatible materials:
Acid chlorides
Hazardous decomposition products:
Metal oxide fume


Information on toxicological effects
Acute toxicity:
No effects known.
LD/LC50 values that are relevant for classification:
No data
Skin irritation or corrosion:
No irritant effect.
Eye irritation or corrosion:
May cause irritation
No sensitizing effects known.
Germ cell mutagenicity:
No effects known.
No classification data on carcinogenic properties of this material is available from the EPA, IARC, NTP, OSHA or ACGIH.
Reproductive toxicity:
No effects known.
Specific target organ system toxicity - repeated exposure:
No effects known.
Specific target organ system toxicity - single exposure:
No effects known.
Aspiration hazard:
No effects known.
Subacute to chronic toxicity:
No effects known.
Additional toxicological information:
To the best of our knowledge the acute and chronic toxicity of this substance is not fully known.


Aquatic toxicity:
No further relevant information available.
Persistence and degradability
No further relevant information available.
Bioaccumulative potential
No further relevant information available.
Mobility in soil
No further relevant information available.
Additional ecological information:
General notes:
Do not allow material to be released to the environment without proper governmental permits.
Do not allow undiluted product or large quantities to reach ground water, water course or sewage system.
Avoid transfer into the environment.
Results of PBT and vPvB assessment
Not applicable.
Not applicable.
Other adverse effects
No further relevant information available.


Waste treatment methods
Consult state, local or national regulations to ensure proper disposal.
Uncleaned packagings:
Disposal must be made according to official regulations.


Not applicable
UN proper shipping name
Not applicable
Transport hazard class(es)
Not applicable
Packing group
Not applicable
Environmental hazards:
Not applicable.
Special precautions for user
Not applicable.
Transport in bulk according to Annex II of MARPOL73/78 and the IBC Code
Not applicable.
Transport/Additional information:
Marine Pollutant (DOT):


Safety, health and environmental regulations/legislation specific for the substance or mixture
GHS label elements
Not applicable
Hazard pictograms
Not applicable
Signal word
Not applicable
Hazard statements
Not applicable
National regulations
All components of this product are listed in the U.S. Environmental Protection Agency Toxic Substances Control Act Chemical substance Inventory.
All components of this product are listed on the Canadian Non-Domestic Substances List (NDSL).
SARA Section 313 (specific toxic chemical listings)
Substance is not listed.
California Proposition 65
Prop 65 - Chemicals known to cause cancer
Substance is not listed.
Prop 65 - Developmental toxicity
Substance is not listed.
Prop 65 - Developmental toxicity, female
Substance is not listed.
Prop 65 - Developmental toxicity, male
Substance is not listed.
Information about limitation of use:
For use only by technically qualified individuals.
Other regulations, limitations and prohibitive regulations
Substance of Very High Concern (SVHC) according to the REACH Regulations (EC) No. 1907/2006.
Substance is not listed.
The conditions of restrictions according to Article 67 and Annex XVII of the Regulation (EC) No 1907/2006 (REACH) for the manufacturing, placing on the market and use must be observed.
Substance is not listed.
Annex XIV of the REACH Regulations (requiring Authorisation for use)
Substance is not listed.
Chemical safety assessment:
A Chemical Safety Assessment has not been carried out.


Safety Data Sheet according to Regulation (EC) No. 1907/2006 (REACH). The above information is believed to be correct but does not purport to be all inclusive and shall be used only as a guide. The information in this document is based on the present state of our knowledge and is applicable to the product with regard to appropriate safety precautions. It does not represent any guarantee of the properties of the product. American Elements shall not be held liable for any damage resulting from handling or from contact with the above product. See reverse side of invoice or packing slip for additional terms and conditions of sale. COPYRIGHT 1997-2016 AMERICAN ELEMENTS. LICENSED GRANTED TO MAKE UNLIMITED PAPER COPIES FOR INTERNAL USE ONLY.

Dysprosium Isotopes

Naturally occurring dysprosium (Dy) has 7 stable isotopes: 156Dy, 158Dy, 160Dy, 161Dy, 162Dy, 163Dy and 164Dy

Nuclide Isotopic Mass Half-Life Mode of Decay Nuclear Spin Magnetic Moment Binding Energy (MeV) Natural Abundance
(% by atom)
138Dy 137.96249(64)# 200# ms Unknown 0+ N/A 1078.07 -
139Dy 138.95954(54)# 600(200) ms Unknown 7/2+# N/A 1095.47 -
140Dy 139.95401(54)# 700# ms ß+ to 140Tb 0+ N/A 1103.54 -
141Dy 140.95135(32)# 0.9(2) s ß+ to 141Tb (9/2-) N/A 1111.62 -
142Dy 141.94637(39)# 2.3(3) s ß+ to 142Tb 0+ N/A 1129.02 -
143Dy 142.94383(21)# 5.6(10) s ß+ to 143Tb (1/2+) N/A 1137.1 -
144Dy 143.93925(3) 9.1(4) s ß+ to 144Tb 0+ N/A 1154.49 -
145Dy 144.93743(5) 9.5(10) s ß+ to 145Tb (1/2+) N/A 1162.57 -
146Dy 145.932845(29) 33.2(7) s ß+ to 146Tb 0+ N/A 1170.65 -
147Dy 146.931092(21) 40(10) s ß+ to 147Tb; ß+ + p to 146Tb 1/2+ N/A 1178.73 -
148Dy 147.927150(11) 3.3(2) min ß+ to 148Tb 0+ N/A 1196.12 -
149Dy 148.927305(9) 4.20(14) min ß+ to 149Tb 7/2(-) N/A 1204.2 -
150Dy 149.925585(5) 7.17(5) min ß+ to 150Tb; a to 146Gd 0+ N/A 1212.28 -
151Dy 150.926185(4) 17.9(3) min ß+ to 151Tb; a to 147Gd 7/2(-) N/A 1220.36 -
152Dy 151.924718(6) 2.38(2) h EC to 152Tb; a to 148Gd 0+ N/A 1228.44 -
153Dy 152.925765(5) 6.4(1) h EC to 153Tb; a to 149Gd 7/2(-) -0.78 1236.52 -
154Dy 153.924424(8) 3.0(15)E+6 y a to 150Gd 0+ N/A 1244.6 -
155Dy 154.925754(13) 9.9(2) h EC to 155Tb 3/2- -0.385 1252.67 -
156Dy 155.924283(7) Observationally Stable - 0+ N/A 1260.75 0.06
157Dy 156.925466(7) 8.14(4) h EC to 157Tb 3/2- -0.301 1268.83 -
158Dy 157.924409(4) Observationally Stable - 0+ N/A 1276.91 0.1
159Dy 158.9257392(29) 144.4(2) d EC to 159Tb 3/2- -0.354 1284.99 -
160Dy 159.9251975(27) Observationally Stable - 0+ N/A 1293.07 2.34
161Dy 160.9269334(27) Observationally Stable - 5/2+ -0.4806 1301.15 18.91
162Dy 161.9267984(27) Observationally Stable - 0+ N/A 1309.22 25.51
163Dy 162.9287312(27) STABLE - 5/2- 0.6726 1317.3 24.9
164Dy 163.9291748(27) STABLE - 0+ N/A 1325.38 28.18
165Dy 164.9317033(27) 2.334(1) h ß- to 165Ho 7/2+ -0.52 1324.14 -
166Dy 165.9328067(28) 81.6(1) h ß- to 166Ho 0+ N/A 1332.22 -
167Dy 166.93566(6) 6.20(8) min ß- to 167Ho (1/2-) N/A 1340.3 -
168Dy 167.93713(15) 8.7(3) min ß- to 168Ho 0+ N/A 1348.38 -
169Dy 168.94031(32) 39(8) s ß- to 169Ho (5/2-) N/A 1347.14 -
170Dy 169.94239(21)# 30# s ß- to 170Ho 0+ N/A 1355.22 -
171Dy 170.94620(32)# 6# s ß- to 171Ho 7/2-# N/A 1363.3 -
172Dy 171.94876(43)# 3# s ß- to 172Ho 0+ N/A 1371.38 -
173Dy 172.95300(54)# 2# s ß- to 173Ho 9/2+# N/A 1370.14 -