Named by Andrew C. Roberts, Joel D. Grice, Robert A. Gault, Alan J. Criddle, Richard C. Erd in 1996 in honor of Joseph Donald Hanawalt (6 July 1902, Royersford, Pennsylvania, USA – 26 June 1987), for his early work in X-ray powder diffraction. He was a metallurgist and an authority on magnesium. He was affiliated with 3M and the University of Michigan, Ann Arbor, Michigan, USA. He developed what would be known as the Hanawalt X-ray Diffraction Method, and was awarded 30 patents and numerous awards.

Type Locality:

ⓘ Clear Creek claim, Goat Mountain, San Benito County, California, USA

This page provides mineralogical data about Hanawaltite.

Hide all sections | Show all sections

Unique IdentifiersHide

Mindat ID:

1813

Long-form identifier:

mindat:1:1:1813:1

IMA Classification of HanawaltiteHide

IMA status:

Approved

IMA Formula:

Hg¹⁺₆Hg²⁺O₃Cl₂

Approval year:

1994

First published:

1996

Type description reference:

Roberts, A. C., Grice, J. D., Gault, R. A., Criddle, A. J., Erd, R. C. (1996) Hanawaltite, Hg¹⁺₆Hg²⁺[Cl,(OH)]₂O₃ — A new mineral from the Clear Creek claim, San Benito County, California: Description and crystal structure. Powder Diffraction, 11 (1) 45-50 doi:10.1017/s0885715600008915

Classification of HanawaltiteHide

Strunz-mindat (2026):

3.DD.15

3 : HALIDES
D : Oxyhalides, hydroxyhalides and related double halides
D : With Hg

Dana 8th ed.:

10.5.13.1

10 : OXYHALIDES AND HYDROXYHALIDES
5 : A_m(O,OH)_pX_q

Mineral SymbolsHide

As of 2021 there are now IMA–CNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.

Symbol	Source	Reference for Standard
Hnw	IMA–CNMNC	Warr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43

Physical Properties of HanawaltiteHide

Lustre:

Metallic

Transparency:

Translucent, Opaque

Colour:

Black to very dark brown-black

Streak:

Dark reddish black

Hardness:

4 on Mohs scale

Tenacity:

Brittle

Cleavage:

Distinct/Good
{001} good

Fracture:

Irregular/Uneven

Density:

9.51 g/cm³ (Calculated)

Optical Data of HanawaltiteHide

Type:

Biaxial

Anisotropism:

Bright metallic blue.

Bireflectance:

Moderate to strong.

Reflectivity:

Wavelength	R₁ (%)	R₂ (%)
400nm	26.2%	37.6%
420nm	25.2%	34.8%
440nm	24.2%	32.5%
460nm	23.3%	30.6%
480nm	22.4%	29.0%
500nm	21.8%	27.7%
520nm	21.2%	26.7%
540nm	20.8%	25.9%
560nm	20.5%	25.2%
580nm	20.3%	24.6%
600nm	20.1%	24.1%
620nm	20.0%	23.7%
640nm	20.2%	23.3%
660nm	20.3%	23.1%
680nm	20.2%	22.9%
700nm	20.0%	22.8%

Graph shows reflectance levels at different wavelengths (in nm). Peak reflectance is 37.6%.
R₁ shown in black, R₂ shown in red

Colour in reflected light:

Gray

Internal Reflections:

May have red-orange internal reflections

Pleochroism:

Weak

Comments:

Bright bluish white to grayish white

Chemistry of HanawaltiteHide

Mindat Formula:

[Hg₂]²⁺₃Hg²⁺(Cl,OH)₂O₃

Element Weights:

Element	% weight
Hg	92.193 %
Cl	4.656 %
O	3.152 %

Calculated from ideal end-member formula.

Elements listed:

Cl, H, Hg, O - search for minerals with similar chemistry

Crystallography of HanawaltiteHide

Crystal System:

Orthorhombic

Class (H-M):

mmm(2/m2/m2/m) - Dipyramidal

Cell Parameters:

a = 11.790(3) Å, b = 13.881(4) Å, c = 6.450(2) Å

Ratio:

a:b:c = 0.849 : 1 : 0.465

Unit Cell V:

1,055.59 Å³ (Calculated from Unit Cell)

Morphology:

Subhedral to anhedral crystals, platy to bladed, striated k || [001].

Comment:

Space Group: P bma.

Crystal StructureHide

Load
Unit Cell | Unit Cell Packed
2x2x2 | 3x3x3 | 4x4x4

View
CIF File Best | x | y | z | a | b | c

Rotation
Stop | Start

Labels
Console Off | On | Grey | Yellow

Data courtesy of the American Mineralogist Crystal Structure Database. Click on an AMCSD ID to view structure

ID	Species	Reference	Link	Year	Locality	Pressure (GPa)	Temp (K)
0015316	Hanawaltite	Roberts A C, Grice J D, Gault R A, Criddle A J, Erd R C (1996) Hanawaltite, Hg1+6Hg2+[Cl,(OH)]2O3 - A new mineral from the Clear Creek claim, San Benito County, California: Description and crystal structure Powder Diffraction 11 45-50		1996	Clear Creek claim, San Benito County, California	0	293
0005606	Hanawaltite	Grice J D (1999) Redetermination of the crystal structure of hanawaltite The Canadian Mineralogist 37 775-778		1999		0	293

CIF Raw Data - click here to close

data_global
_chemical_name_mineral 'Hanawaltite'
loop_
_publ_author_name
'Roberts A C'
'Grice J D'
'Gault R A'
'Criddle A J'
'Erd R C'
_journal_name_full 'Powder Diffraction'
_journal_volume 11 
_journal_year 1996
_journal_page_first 45
_journal_page_last 50
_publ_section_title
;
 Hanawaltite, Hg1+6Hg2+[Cl,(OH)]2O3 - A new mineral from
 the Clear Creek claim, San Benito County, California:
 Description and crystal structure
;
_database_code_amcsd 0015316
_chemical_compound_source 'Clear Creek claim, San Benito County, California'
_chemical_formula_sum 'Hg7 Cl2 O3'
_cell_length_a 11.777
_cell_length_b 13.891
_cell_length_c 6.460
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 1056.819
_exptl_crystal_density_diffrn      9.572
_symmetry_space_group_name_H-M 'P b m a'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2-x,1/2+y,z'
  '1/2+x,1/2-y,-z'
  '1/2+x,y,-z'
  '1/2-x,-y,z'
  'x,1/2-y,z'
  '-x,1/2+y,-z'
  '-x,-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
Hgl   0.11670   0.58310   0.47120   0.01200
Hg2   0.29110   0.62950   0.67590   0.01900
Hg3   0.03780   0.75000   0.13400   0.01600
Hg4   0.24480   0.25000   0.15100   0.02200
Hg5   0.00000   0.50000   0.00000   0.01000
Cl1   0.25000   0.50000   0.08400   0.01400
Cl2   0.44095   0.75000   0.32900   0.03600
O1   0.34400   0.75000  -0.10000   0.02000
O2  -0.02000   0.54500   0.28000   0.02000

X-Ray Powder DiffractionHide

Powder Diffraction Data:

d-spacing	Intensity
3.053 Å	(100)
5.25 Å	(80)
2.954 Å	(70)
3.164 Å	(60)
2.681 Å	(50)
2.411 Å	(50)
4.35 Å	(40)

Locality:

Clear Creek claim, Goat Mountain, San Benito County, California, USA

Reference:

Geological EnvironmentHide

Paragenetic Mode(s):

Paragenetic Mode	Earliest Age (Ga)
Stage 7: Great Oxidation Event	<2.4
47a : [Near-surface hydration of prior minerals]
47g : [Halogen-bearing surface weathering minerals]
47h : [Near-surface oxidized, dehydrated minerals]

Type Occurrence of HanawaltiteHide

Type Locality:

ⓘ Clear Creek claim, Goat Mountain, San Benito County, California, USA

Place of Conservation of Type Material:

Canadian Geological Survey, Ottawa, Canada, 67396.

Geological Setting of Type Material:

Alteration product of cinnabar, in a mercury deposit in silicate-carbonate rock hydrothermally altered from serpentinite.

Associated Minerals at Type Locality:

Calomel	Cinnabar	Magnesite	Montroydite	Native Mercury
Quartz

Reference:

Synonyms of HanawaltiteHide

IMA1994-036

Other Language Names for HanawaltiteHide

Dutch:Hanawaltiet

German:Hanawaltit

Russian:Ханавальтит

Spanish:Hanawaltita

Related Minerals - Strunz-mindat Grouping Hide

3.DD.	Mikecoxite	[CHg₄]OCl₂	Mon. 2/m
3.DD.05	Eglestonite	[Hg₂]²⁺₃OCl₃(OH)	Iso. m3m(4/m32/m) : Ia3d
3.DD.05	Kadyrelite	[Hg₂]²⁺₃OBr₃(OH)	Iso. m3m(4/m32/m) : Ia3d
3.DD.10	Poyarkovite	[Hg₂]²⁺₃Cl₂O₂	Mon. 2/m : B2/b
3.DD.20	Terlinguaite	[Hg₃]⁴⁺Hg²⁺Cl₂O₂	Mon. 2/m : B2/m
3.DD.25	Pinchite	Hg²⁺₅Cl₂O₄	Orth. mmm(2/m2/m2/m) : Ibam
3.DD.30	Gianellaite	[(Hg₂N)₂](SO₄)(H₂O)_x	Iso. 43m : F43m
3.DD.30	Mosesite	(Hg₂N)(Cl,SO₄,MoO₄) · H₂O	Iso. 43m : F43m
3.DD.35	Kleinite	(Hg₂N)(Cl,SO₄) · nH₂O	Hex. 6/mmm(6/m2/m2/m) : P6₃/mmc
3.DD.40	Tedhadleyite	[Hg₂]²⁺₅Hg²⁺I₂(Cl,Br)₂O₄	Tric. 1
3.DD.45	Vasilyevite	[Hg₂]²⁺₁₀I₃Br₂Cl[CO₃]O₆	Tric. 1 : P1
3.DD.50	Aurivilliusite	[Hg₂]²⁺Hg²⁺₂(I,Br,Cl)₂O₂	Mon. 2/m : B2/b
3.DD.55	Terlinguacreekite	Hg²⁺₃Cl₂O₂	Orth.
3.DD.60	Kelyanite	[Hg]²⁺₆Sb³⁺BrCl₂O₆	Trig. 3 : P3
3.DD.65	Comancheite	Hg²⁺₅₅N^3-₂₄(NH₂,OH)₄(Cl,Br)₃₄	Orth.
3.DD.70	Gaildunningite	Hg²⁺₃[NHg²⁺₂]₁₈(Cl,I,OH,Br,S)₂₄	Orth. mmm(2/m2/m2/m)

Other InformationHide

Notes:

Decrepitates on exposure to sunlight, photoreducing to mercury.

Special Storage/
Display Requirements:

Avoid exposure to light.

Health Risks:

No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.

Internet Links for HanawaltiteHide

mindat.org URL:

https://www.mindat.org/min-1813.html
Please feel free to link to this page.

Search Engines:

Look for Hanawaltite on Google

Look for Hanawaltite images on Google

Look for Hanawaltite on Bing

Look for Hanawaltite images on Bing

Look for Hanawaltite on DuckDuckGo

Look for Hanawaltite images on DuckDuckGo

Look for Hanawaltite in the Rock H. Currier Digital Library

External Links:

Look for Hanawaltite on Webmineral

Look for Hanawaltite on Wikipedia

Look for Hanawaltite on Mineralien Atlas

Raman and XRD data at RRUFF project

References and PDF downloads at RRUFF project

American Mineralogist Crystal Structure Database

Handbook of Mineralogy page PDF

Mineral Dealers:

Buy from D. Joyce minerals

References for HanawaltiteHide

Reference List:

Grice, J.D. (1999) Redetermination of the crystal structure of hanawaltite. The Canadian Mineralogist: 37: 775-778.

Jambor, J.L., Kovalenker, V.A., Puziewics, J., Roberts, A.C. (1996) New mineral names. American Mineralogist: 81: 1282-1286.

Mandarino, Joseph A. (1996) Abstracts of New Mineral Descriptions. The Mineralogical Record, 27 (6) 463-466pp.463-464

(2005) Hanawaltite. Handbook of Mineralogy. Mineralogical Society of America

Localities for HanawaltiteHide

Showing 1 localities.

This map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the

symbol to view information about a locality. The

symbol next to localities in the list can be used to jump to that position on the map.

Hide all sections | Show all sections

Locality ListHide

- This locality has map coordinates listed.

- This locality has estimated coordinates. ⓘ - Click for references and further information on this occurrence. ? - Indicates mineral may be doubtful at this locality.

- Good crystals or important locality for species.

- World class for species or very significant. (TL) - Type Locality for a valid mineral species. (FRL) - First Recorded Locality for everything else (eg varieties). ~~Struck out~~ - Mineral was erroneously reported from this locality. Faded * - Never found at this locality but inferred to have existed at some point in the past (e.g. from pseudomorphs).

All localities listed without proper references should be considered as questionable.

USA (TL)

California

San Benito County

Goat Mountain

ⓘ Clear Creek claim (TL)

Canadian Mineralogist: 34: 61-72. +2 other references

Mindat.org® is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization. Mindat® and mindat.org® are registered trademarks of the Hudson Institute of Mineralogy.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2026, except where stated. Most political location boundaries are © OpenStreetMap contributors. Mindat.org relies on the contributions of thousands of members and supporters. Founded in 2000 by Jolyon Ralph and Ida Chau.
Content on this site may not be used to train, fine-tune, or otherwise develop artificial intelligence or machine learning models without prior written permission - see our Terms & Conditions.
To cite: Ralph, J., Von Bargen, D., Martynov, P., Zhang, J., Que, X., Prabhu, A., Morrison, S. M., Li, W., Chen, W., & Ma, X. (2025). Mindat.org: The open access mineralogy database to accelerate data-intensive geoscience research. American Mineralogist, 110(6), 833–844. doi:10.2138/am-2024-9486.
Privacy Policy - Terms & Conditions - Contact Us / DMCA issues - Report a bug/vulnerability Current server date and time: September 1, 2026 14:33:33 Page updated: August 19, 2026 03:11:52

Go to top of page

Hanawaltite