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Trigonal System - Unknown or Uncertain Class

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Axial Configuration	Paper Model

Partial listing of all valid minerals that crystallize in the Trigonal System. There is not enough known about them to permit assignment into a class.

System	Class Name	AXES				Planes	Center	Hermann- Maugin Symbols
System	Class Name	2-Fold	3-Fold	4-Fold	6-Fold	Planes	Center	Hermann- Maugin Symbols
Trigonal	Pyramidal	-	1	-	-	-	-	3
	Rhombohedral	-	1	-	-	-	yes	-3
	Ditrigonal Pyramidal	-	1	-	-	3	-	3m
	Trapezohedral	3	1	-	-	-	-	32
	Hexagonal Scalenohedral	3	1	-	-	3	yes	3 2/m

**30 Minerals From the H-M Class Trigonal - Unknown or Uncertain**
Mineral	Space Grp	a	c	Z	Vol (Ang3)	Calc Dens
Alunite	R 3m R 3m	6.9700	17.3800	4	731.2	3.76
Babkinite	P 3P 3m	4.1910	39.6000	3	602.4	8.07
Cesarolite	HEX-R	2.8110	20.3860	1	139.5	5.98
Coombsite	R 3 or R 3	11.8280	29.1460	3	3531.3	3.00
Cronusite	Rm R 3m or R 32	3.3260	33.2900	3	318.9	2.53
Daqingshanite-(Ce)	R 3m R 3m or R 32	10.0580	9.2250	4	808.2	4.52
Desautelsite	R 3m or R 3m	6.2300	46.7800	3	1572.4	2.09
Droninoite	R 3m R 3m or R 32	6.2060	46.1840	6	1540.4	2.86
Ernienickelite	R 3 or R 3	7.5140	20.5200	6	1003.4	3.87
Francoanellite	R 3c or R 3c	8.7100	82.5000	6	5420.3	2.28
Geerite	R 3m R 3m or R 32	3.8300	46.8400	3	595.0	5.60
Glaucocerinite	Unk (HEX-R)	3.0570	32.5200		263.2	2.32
Jianshuiite	R 3 or R 3	7.5400	20.8200	6	1025.1	3.57
Karchevskyite	P 3 P 31m P 3₁m P 3₁2	16.0550	25.6600	3	5728.1	2.18
Magnesionigerite-6N6S	Unk	5.6920	13.7800	1	386.6	4.14
Marinellite	P 3₁c or P 2c	12.8800	31.7610	1	4563.1	2.43
Mathewrogersite	R 3R 3-R 32R 3mR 3m-	8.4570	45.9700	3	2847.3	4.69
Melanocerite-(Ce)	Unk (HEX-R)	9.3500	6.8800	2	520.9	5.76
Muskoxite	Unk (pseudo HEX-R)	3.0700	4.6000		37.6	3.46
Nanlingite	R 3m R 3m	10.2400	25.7600	12	2339.3	3.91
Orlymanite	P 3-P 3	9.6000	35.9200	5	2866.9	2.92
Philipsbornite	R 3m-R 3m	7.1100	17.0500	3	746.4	4.46
Romanite	Trig ?
Stepanovite	Unk	9.8400	36.6700	6	3074.9	1.69
Sztrokayite	Trig ?
Tegengrenite	R 3 or R 3-	16.1960	14.9480	42	3395.7	4.50
Truscottite	p3 or p3	9.7310	18.8360	1	1544.7	2.54
Vanoxite	Unk
Zhemchuzhnikovite	Unk	16.6700	12.5100	6	3010.6	1.63
Zirklerite	Unk

(* - Mineral Name is Not IMA Approved)
(! - New Dana Classification Number Has Been Changed or Added)
(? - IMA Discredited Mineral Species Name

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