Rämepuro (Hattu schist belt)

North Karelia, Ilomantsi, Hattu schist belt, Finland

Orogenic goldAu

Type: Orogenic gold in metasediments and felsic porphyries

Archaean schist belt (2.76 to 2.72 Ga) of the Karelian domain, with felsic to intermediate volcano-sedimentary rocks cut by tonalites, granodiorites and felsic porphyries; Au-Bi-Te gold in shear zones, older than the metamorphic peak (500 to 600 °C, 3 to 5 kbar, about 2.70 Ga). Active mine (reserve 0.169 Mt at 2.1 g/t); tourmalinized metasediments and mineralized felsic porphyries. Molnár et al. (2016): tourmaline δ11B, sulphide δ34S and chalcopyrite δ65Cu.

δ11B in ‰ (per mil) Values of the same system

Standard : NIST SRM 951

Value	Range	n	Mineral or matrix	Source
−11.1 ± 1.1 ‰	−13 / −9.6 ‰	18	vein tourmaline in a felsic porphyry (type 2) (10_RAMT) Mean and standard deviation recalculated from 18 analyses, -13.0 to -9.6 (-9.8; -11.7; -11.4; -10.2; -13.0; -10.6; -9.7; -11.5; -9.7; -12.0; -9.6; -11.8; -11.3; -10.1; -12.4; -11.0; -11.0; -12.8). 10 core and 8 rim analyses; published mean -11.1 ‰. Highest values of the belt.	Molnár et al. (2016), Boron, sulphur and copper isotope systematics in the orogenic gold …

δ34S in ‰ (per mil) Values of the same system

Standard : V-CDT

Value	Range	n	Mineral or matrix	Source
2 ± 0.4 ‰	1.4 / 2.6 ‰	7	pyrite of metasediments Mean and standard deviation recalculated from the means of 2 samples (M23521 (a) +2.3 (n = 5); M23521 (b) +1.7 (n = 2)), i.e. 7 spot analyses from +1.4 to +2.6 ‰.	Molnár et al. (2016), Boron, sulphur and copper isotope systematics in the orogenic gold …
2.2 ± 0.2 ‰	1.4 / 3.2 ‰	9	pyrrhotite of metasediments Mean and standard deviation recalculated from the means of 2 samples (M23521 +2.0 (n = 5); M23522 +2.3 (n = 4)), i.e. 9 spot analyses from +1.4 to +3.2 ‰.	Molnár et al. (2016), Boron, sulphur and copper isotope systematics in the orogenic gold …
0.8 ± 0.5 ‰	0 / 1.5 ‰	8	chalcopyrite of metasediments Published mean and standard deviation of 8 spot analyses (sample M23522), 0.0 to +1.5 ‰.	Molnár et al. (2016), Boron, sulphur and copper isotope systematics in the orogenic gold …
1.9 ± 1 ‰	0.2 / 3.2 ‰	17	pyrrhotite of feldspar porphyries Mean and standard deviation recalculated from the means of 3 samples (M23598 +3.0 (n = 4); M23375 +1.6 (n = 5); 10-RAMT +1.0 (n = 8)), i.e. 17 spot analyses from +0.2 to +3.2 ‰.	Molnár et al. (2016), Boron, sulphur and copper isotope systematics in the orogenic gold …
2.4 ± 1.1 ‰	1.6 / 3.2 ‰	2	chalcopyrite of feldspar porphyries Published mean and standard deviation of 2 spot analyses (sample M23598), +1.6 to +3.2 ‰.	Molnár et al. (2016), Boron, sulphur and copper isotope systematics in the orogenic gold …

δ65Cu in ‰ (per mil) Values of the same system

Standard : NIST SRM 976

Value	Range	n	Mineral or matrix	Source
−0.28 ± 0.39 ‰	−0.73 / 0.33 ‰	6	chalcopyrite of metasediments (M23522) Mean and standard deviation recalculated from 6 analyses, -0.73 to +0.33 (-0.61; -0.26; -0.03; -0.73; +0.33; -0.35). Positive values mostly in felsic intrusive rocks, negative in metasediments; no correlation with δ34S according to the authors.	Molnár et al. (2016), Boron, sulphur and copper isotope systematics in the orogenic gold …

Deposits of the same type

Cite this page

IsoFind Atlas (2026). Rämepuro (Hattu schist belt), isotope signatures. https://www.isofind.tech/isotopes/en/deposits/ramepuro-ceinture-de-hattu/ (accessed 2026-10-19).

@misc{isofind2026ramepurohattuschistbeltisotop,
  title = {Rämepuro (Hattu schist belt), isotope signatures},
  author = {{IsoFind Atlas}},
  year = {2026},
  url = {https://www.isofind.tech/isotopes/en/deposits/ramepuro-ceinture-de-hattu/},
  note = {Accessed 2026-10-19}
}

Updated : 2026-10-19