Gambatesa and Molinello

Location - Italy

Age (of portore) - 146 Ma

Original size - 0.36 million tonnes of Mn

References

Bonatti, E., Zerbi, M., Kay, R., and Rydell, H., 1976, Metalliferous deposits from the Apennine ophiolites: Mesozoic equivalents of modern deposits from oceanic spreading centers: Geological Society of America Bulletin, v. 87, p. 83-94.

Marchesni, M., and Pagano, R., 2001, The Val Graveglia manganese district, Liguria, Italy: Mineralogical Record, v. 32, p. 349-379.

 

major elements - trace elements - rare-earth elements

Major Elements, oxide percent

 

Gambatesa

 

%

%

%

%

%

%

%

%

%

%

%

MnO
Fe2O3t
SiO2
Al203
CaO
MgO
K2O
Na2O
TiO2
P205
LOI

Average

 

Both occurrences
30.12
0.68
62.15
1.10
1.24
0.25
0.11
0.17
0.05
   

Gambatesa average (MnO>10%)

15.63 1.07 77.14 1.80 0.82 0.37 0.12 0.27 0.05  
Z-52b massive Mn ore 24.02 2.22 61.82 4.59 1.72 1.21 0.27 0.64 0.13  
Z-46b banded Mn ore 20.04 0.81 75.09 0.79 0.88 0.07 0.05 0.07 0.03  
Z·51 massive Mn ore 12.20 0.43 82.79 0.64 0.32 0.15 0.18 0.14 0.02  
Z-45 chert + Mn ore 11.72 0.93 81.93 2.61 0.29 0.35 0.03 0.43 0.06  
Z.46r banded Mn ore + chert 10.19 0.96 84.07 0.38 0.90 0.08 0.05 0.06 0.04  
Z·50 chert + Mn ore 6.53 0.93 88.99 2.49 0.14 0.33 0.04 0.45 0.05 0.76  
Z-52r chert + Mn ore 6.15 2.43 80.86 5.50 1.11 1.91 0.16 0.70 0.14  
Z·47 chert + Mn ore 4.80 0.79 88.99 0.09 0.70 0.10 0.09 0.11 0.03 0.64  
Z-53 red chert 1.60 5.15 81.72 5.71 0.50 1.09 0.30 0.17 0.20  
Z·44 red chert 0.61 3.29 84.07 6.69 0.63 1.19 0.11 1.90 0.15  
Z-48 red chert 0.36 1.03 88.78 1.00 0.70 0.17 0.20 0.27 0.05  
Z-49 red chert 0.25 1.36 90.92 3.31 0.15 0.51 0.09 1.10 0.11  
 

Molinello average (MnO>10%)

44.60 0.30 47.16 0.41 1.65 0.13 0.10 0.08 0.04    
Z-36 massive Mn ore
61.49
0.11 30.16 0.45 1.85 0.12 0.05 0.07 0.01  
Z-41 massive Mn ore 59.56 0.43 29.52 1.25 1.40 0.41 0.12 0.16 0.02  
Z·17 massive Mn ore 59.56 0.09 31.02 0.11 2.99 0.07 0.05 0.10 0.01  
Z-14 massive Mn ore 57.64 0.13 28.45 0.40 2.10 0.10 0.15 0.12 0.01  
Z·22 massive Mn ore 54.76 0.11 37.44 0.09 1.72 0.03 0.15 0.06 0.01  
Z·27 massive Mn ore 53.79 0.29 37.44 0.15 1.67 0.07 0.09 0.04 0.01  
Z-12 massive Mn ore + carbonate 50.44 0.26 42.36 0.36 1.39 0.07 0.09 0.05 0.30  
Z-39b brecciated chert + Mn ore 38.90 0.61 53.69 0.53 1.30 0.12 0.11 0.08 0.02  
Z·2 brecciated chert + Mn ore 25.55 0.19 67.38 0.60 1.11 0.30 0.05 0.10 0.02  
Z-30 massive Mn ore 18.74 0.10 74.44 0.13 1.72 0.07 0.15 0.02 0.01  
Z-39r brecciated chert + Mn ore 10.19 0.94 86.85 0.38 0.90 0.08 0.09 0.07 0.04  
Z-33 chert + Mn ore 9.41 0.06 86.85 0.09 0.45 0.03 0.15 0.04 0.01  
Z·1b chert + banded Mn ore 4.27 0.59 94.34 0.49 0.10 0.05 0.05 0.10 0.01 0.34  
Z·1r chert + banded Mn ore 3.12 0.61 94.98 0.45 0.08 0.07 0.05 0.14 0.01 0.30  
Z-42 brecciated chert 1.59 9.29 64.18 15.00 0.25 2.17 3.30 3.20 0.65  
Z-11 red chert 0.67 2.00 91.34 2.25 0.29 0.46 0.30 0.70 0.10  
Z·43 red chert 0.66 7.43 71.02 12.70 0.29 1.61 2.70 2.90 0.48    

 

Trace elements, ppm

 

 

ppm

ppm

ppm

ppm

ppm

ppm

ppm

ppm

ppm

ppm

ppm

ppm

 

Ba
Co
Cr
Cu
Ni
Sc
Th
U
V
Y
Zn
Zr

avg - both

1215 106 21 232
71
        7 58  

Gambatesa avg (MnO>10%)

803
139
27
136
2
7
57
 
Z-52b 650 350 35 62 75 3     14 68
Z-46b    
Z·51 1,600 43 15 97 20 b.d.     4 21
Z-45 160 25 30 250 53 b.d.     1.5 82
Z.46r    
Z·50 400 35 17 240 35 b.d.     26 1.5 30 30
Z-52r 350 600 43 130 15 3     14 86
Z·47 1450 85 19 150 25 b.d.     125 1.5 20 26
Z-53 250 90 30 230 75 5     250 10 54 60
Z·44 200 35 45 175 45 5     30 6 40 30
Z-48 930 19 12 78 10 b.d.     63 1.5 17 16
Z-49 135 13 25 25 30 b.d.     45 3 29 12

Molinello avg    (MnO>10%)

1627
73
15
327
93
0.11
3.64
7
59
 
Z-36 850 60 2.5 120 105 b.d. 0.05 3.49 16 72
Z-41 200 125 30 240 80 b.d. 19 68
Z·17 3,500 80 5 310 39 b.d. 0.121 2.9 1.5 50
Z-14 2,500 65 5 305 70 b.d. 0.049 3.78 1.5 70
Z·22 750 90 5 490 40 b.d. 1.5 49
Z·27 2,500 75 8 180 75 b.d. 0.221 4.39 17 51
Z-12 5,500 175 5 720 135 b.d. 1.5 62
Z-39b 550 50 80 140 115 b.d. 12 125
Z·2 700 60 15 950 55 b.d. 1.5 36
Z-30 450 4 0 2.5 260 25 1.5 5 37
Z-39r 400 20 10 140 50 b.d. 1.5 30
Z-33 450 20 10 240 25 b.d. 3 21
Z·1b 1,140 19 20 360 25 b.d. 20 1.5 20 16
Z·1r 1,400 11 14 240 25 b.d. 17 1.5 25 14
Z-42 450 165 113 95 130 13 110 8 53 135
Z-11 350 16 25 160 25 b.d. 45 1.5 12 25
Z·43 350 100 105 55 125 12     170 14 73 130

blank or nr = not reported; bd = below detection

Rare-earth elements, ppm

 

Sample
La
Ce
Pr
Nd
Sm
Eu
Gd
Tb
Dy 
Ho 
Er 
Tm 
Yb
Lu
Z17
1.72 5 2.74 0.68 0.173 0.099
0.23