Norsk versjon
	THE ORE DATABASE
	Occurence 5045 - 027 Hotjern
	(Object Id: 331) (Last updated: 16.05.2006)

Operations

	From - To	Activity	Comments
	1972 - 1972	Geophysics	Company/Institution :NGU (helikopter)
	1973 - 1973	Geophysics	Company/Institution :NGU
	1975 - 1975	Geophysics	Company/Institution :Grong Gruber A/S
	1991 - 1991	Sampling	Company/Institution :NGU
	1996 - 1996	Sampling	Company/Institution :NGU

Mineralization

	Genesis:	Volcex	Form:	Layer
	Main texture:	Structureless	Min. distribution:	Semi-massive (20-50 % ore minerals)

Main grain size:

Fine grained (< 1 mm)

Main alteration:

No country rock alteration

	Strike/Dip:	18 / 15	Direction:
			Plunge:

Stratigraphic classification of host rock

Era:

Period:

	Province:	Caledonides
	Geotec.unit:	Trondheim Nappe Complex
	Tectonic complex:	Gula Nappe
	Igneous complex:

Group:

Formation:

Mineralogy

	Relationship	Mineral	Amount
	Gangue mineral	Amphibole	Major mineral (>10%)
	Gangue mineral	Plagioclase	Major mineral (>10%)
	Gangue mineral	Quartz	Subordinate mineral (1-10%)
	Gangue mineral	Garnet	Accessory mineral (<1%)
	Ore mineral	Pyrrhotite	Major mineral (>10%)
	Ore mineral	Pyrite	Subordinate mineral (1-10%)
	Ore mineral	Magnetite	Accessory mineral (<1%)

Lithology:

	Relationship	Rock	Origin
	Wall rock	Kvarts-feltspat gneis	Extrusive Original rock :Keratophyre
			Metamorphic facies :Amphibolite
	Wall rock	Amfibolitt	Extrusive Original rock :Basalt
			Metamorphic facies :Amphibolite

Structures

	Location:	Type:	Orientation(360 gr.):	Relation to min.:
	Wall rock	Foliation	Strike/Dip :18 / 15	Post-mineralisation ;...Effect :None

Information(s) in free text format

Free text

Skjerpet ligger 2-300 m øst for Namsen, rett syd for Gartland, 4 m fra nordvestkanten av Hotjernet. Tjernet ligger i en markert kløft med bratte skrenter i vest og i øst. Det er dårlig blottet omkring skjerpet som består av en 1x1 m utsprengt grop. I en hornblenderik amfibolitt finnes en tilnærmet flattliggende, tilnærmet N-S orientert, minimum 1 m mektig sone som består vesentlig av magnetkis, dels massiv malm og dels breksjemalm. I fortsettelsen av malmsonen lengre sør finnes en kvarts-feltspat rik gneis som kan representere en sur vulkanitt. Geofysiske målinger antyder en dagnær, flattliggende, god leder. Utstrekningen overstiger ikke 200 m. Nordøst for hovedskjerpet er det prøvetatt en mineralisering med sulfid-disseminasjon i amfibolitt (Prøvelokalitet 1, LS91008-LS91011).

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	NT0387.01	Dump	Sampler: Sandstad, J.S./...Size(kg): 2 Comment: Pyrrhotite ore, massive, fine grained, idiomorph pyrite (1-3 mm), few rock fragments. No. of registrated element analyses = 1
	NT0387.02	Dump	Sampler: Sandstad, J.S./...Size(kg): 2 Comment: Pyrrhotite ore, semi-massive to strong disseminations, quartz-feldspar rich matrix, with contact to garnet amphibolite og felsic rock. No. of registrated element analyses = 1
	NT0387.03	Dump	Sampler: Sandstad, J.S./...Size(kg): 2 Comment: Pyrrhotite ore, stockwerk, dark green rock fragments and quartz eyes. No. of registrated element analyses = 1

NB! All analyse values are shown at the end of the printout.:

Name of Sample point: Hotjern øst

(Object Id: 6810 27,00,01)

Location

County:

Trøndelag

Municipality:

Grong (5045)

Map 1:50000:

Harran (1824-3)

Map 1:250000:

Grong

Coordinate system:

EU89-UTM Zone 33

East:

374731 m.

North:

7157229 m.

Longitude:

12.3900080

Latitude:

64.5172350

Show on map

Resource

	Resource Type:	Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn)	Resource Subtype:	Sulphides
			Element(s):	Kis

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	LS91008	Bedrock	Sampler: Størseth, L.R. Comment: Pyrrhotite dissemination in coarse grained amphibolite. No. of registrated element analyses = 1
	LS91009	Bedrock	Sampler: Størseth, L.R. Comment: Weak pyrrhotite dissemination in amphibolite. No. of registrated element analyses = 1
	LS91010	Bedrock	Sampler: Størseth, L.R. Comment: Pyrrhotite in quartz vein. No. of registrated element analyses = 1
	LS91011	Bedrock	Sampler: Størseth, L.R. Comment: Pyrrhotite-(pyrite) dissemination in amphibolite. No. of registrated element analyses = 1

NB! All analyse values are shown at the end of the printout.:

---

Analyse Results

from

Deposit Area 5045 - 027 Hotjern

Element analyses

( *=parts pr. million, #=parts pr.billion, Negative values means below detection limit value.)

Sample No.	Sample Type	Cu*	Zn*	Pb*	Co*	Ni*	Ag*	Au#
LS91008	Bedrock	105	178	30	31	50	.2	4.0
LS91009	Bedrock	24	139	6	16	34	.1	2.0
LS91010	Bedrock	53	13	9	16	16	.1	3.0
LS91011	Bedrock	767	121	110	5	44	.2	3.0
NT0387.01	Dump	273	632	29	52	146	1.0	11.0
NT0387.02	Dump	166	775	17	9	54	.3	-1.0
NT0387.03	Dump	85	864	50	20	57	.3	16.0

------------------

Sample No.	Pt#	Pd#	Rh#	As*	Cd*	Ba*	Mo*	Sb*	Bi*
LS91008	1.0	1.0		2	.2	80	2.00	2	2
LS91009	1.0	2.0		2	.2	26	1.00	2	2
LS91010	1.0	2.0		2	.3	15	5.00	2	2
LS91011	1.0	3.0		2	.2	20	1.00	2	2
NT0387.01	8.0	2.0	-1.0	562	-.2	8	5.00	-2	3
NT0387.02	6.0	-1.0	-1.0	80	2.3	15	5.00	6	-2
NT0387.03	4.0	7.0	-1.0	612	1.0	10	-1.00	-2	-2

------------------

Sample No.	S%	V*	Cr*	Mn*	Fe%	Th*	U*	W*	Sr*
LS91008	1.05	149	66	450	6.91	1.00	5.00	1	12.0
LS91009	.05	133	79	670	7.70	1.00	5.00	1	22.0
LS91010	.97	7	20	157	1.38	1.00	5.00	2	2.0
LS91011	5.15	108	25	406	12.07	1.00	5.00	1	11.0
NT0387.01	29.40	21	3	66	39.31	-2.00	15.00	-2	7.0
NT0387.02	8.09	32	9	304	13.42	4.00	-5.00	-2	13.0
NT0387.03	33.92	19	6	29	23.66	3.00	6.00	-2	5.0

------------------

Sample No.	La*	B*
LS91008	2.00	5
LS91009	2.00	5
LS91010	2.00	2
LS91011	3.00	6
NT0387.01	5.00	16
NT0387.02	16.00	7
NT0387.03	7.00	15

---

The fact sheet was created on 04.05.2024

Questions or comments regarding the fact sheet can be emailed to: ressursdatabaser@ngu.no

Copyright © 2024 Geological Survey of Norway