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Biotite from
Erongo Mountains, Erongo Region, Namibia

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Predictive Mineralogy

Phlogopite, etc.

Erongo Mountains, Erongo Region, Namibia

Biotite, etc.

Erongo Mountains, Erongo Region, Namibia

Biotite, etc.

Erongo Mountains, Erongo Region, Namibia

Biotite, etc.

Erongo Mountains, Erongo Region, Namibia

Phlogopite, etc.

Erongo Mountains, Erongo Region, Namibia

Biotite, etc.

Erongo Mountains, Erongo Region, Namibia

Biotite, etc.

Erongo Mountains, Erongo Region, Namibia

Phlogopite, etc.

Erongo Mountains, Erongo Region, Namibia

Biotite, etc.

Erongo Mountains, Erongo Region, Namibia

Biotite, etc.

Erongo Mountains, Erongo Region, Namibia

Biotite, etc.

Erongo Mountains, Erongo Region, Namibia

Locality type:

Mountain

Classification

Species:

'Biotite' (not an IMA approved species)

Formula:

K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂

Age information

Maximum recorded age:

146.9 ± 5.4 Ma

Minimum recorded age:

19.9 ± 4 Ma

Sample ages:

	Recorded age	Geologic Time	Sample	Dating method
1	19.9 ± 4 Ma	Miocene	-	Ar-Ar
2	33.2 ± 2.9 Ma	Oligocene	-	Ar-Ar
3	77.1 ± 2.3 Ma	Late/Upper Cretaceous	-	Ar-Ar
4	136 ± 5.5 Ma	Early/Lower Cretaceous	-	Ar-Ar
5	135.8 ± 2.4 Ma	Early/Lower Cretaceous	-	Ar-Ar
6	132.5 ± 0.1 Ma	Early/Lower Cretaceous	-	Ar-Ar
7	132.8 ± 0.2 Ma	Early/Lower Cretaceous	-	Ar-Ar
8	136.8 ± 0.5 Ma	Early/Lower Cretaceous	-	Ar-Ar
9	113.1 ± 1.3 Ma	Early/Lower Cretaceous	-	Ar-Ar
10	30.9 ± 4.1 Ma	Oligocene	-	Ar-Ar
11	63.2 ± 4.8 Ma	Paleocene	-	Ar-Ar
12	123.7 ± 1.8 Ma	Early/Lower Cretaceous	-	Ar-Ar
13	136.2 ± 1.3 Ma	Early/Lower Cretaceous	-	Ar-Ar
14	132.4 ± 0.2 Ma	Early/Lower Cretaceous	-	Ar-Ar
15	133.4 ± 0.2 Ma	Early/Lower Cretaceous	-	Ar-Ar
16	134.8 ± 0.3 Ma	Early/Lower Cretaceous	-	Ar-Ar
17	146.9 ± 5.4 Ma	Late Jurassic	-	Ar-Ar
18	123 ± 14.7 Ma	Early/Lower Cretaceous	-	Ar-Ar
19	126.2 ± 36.7 Ma	Early/Lower Cretaceous	-	Ar-Ar
20	62.4 ± 3.7 Ma	Paleocene	-	Ar-Ar
21	133.7 ± 0.2 Ma	Early/Lower Cretaceous	-	Ar-Ar
22	133 ± 0.2 Ma	Early/Lower Cretaceous	-	Ar-Ar
23	133.1 ± 0.3 Ma	Early/Lower Cretaceous	-	Ar-Ar
24	134.3 ± 0.2 Ma	Early/Lower Cretaceous	-	Ar-Ar
25	132 ± 0.2 Ma	Early/Lower Cretaceous	-	Ar-Ar
26	126.1 ± 0.4 Ma	Early/Lower Cretaceous	-	Ar-Ar
27	113.2 ± 1.9 Ma	Early/Lower Cretaceous	-	Ar-Ar
28	137.2 ± 8.5 Ma	Early/Lower Cretaceous	-	Ar-Ar
29	146.5 ± 14.6 Ma	Late Jurassic	-	Ar-Ar
30	132.4 ± 0.4 Ma	Early/Lower Cretaceous	-	Ar-Ar
31	133.8 ± 0.6 Ma	Early/Lower Cretaceous	-	Ar-Ar
32	132.3 ± 1.3 Ma	Early/Lower Cretaceous	-	Ar-Ar
33	132.6 ± 1 Ma	Early/Lower Cretaceous	-	Ar-Ar
34	133.3 ± 1.1 Ma	Early/Lower Cretaceous	-	Ar-Ar
35	133.1 ± 1.1 Ma	Early/Lower Cretaceous	-	Ar-Ar

Sample references:

1	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
2	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
3	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
4	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
5	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
6	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
7	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
8	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
9	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
10	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
11	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
12	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
13	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
14	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
15	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
16	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
17	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
18	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
19	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
20	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
21	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
22	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
23	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
24	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
25	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
26	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
27	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
28	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
29	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
30	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
31	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
32	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
33	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
34	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x
35	-	Wigand, Marcus, Schmitt, Axel K., Trumbull, Robert B., Villa, Igor M., Emmermann, Rolf (2004) Short-lived magmatic activity in an anorogenic subvolcanic complex: 40Ar/39Ar and ion microprobe U–Pb zircon dating of the Erongo, Damaraland, Namibia. Journal of Volcanology and Geothermal Research, 130 (3) 285-305 doi:10.1016/s0377-0273(03)00310-x

Confirmation

Validity:

Believed Valid

Associated Minerals Based on Photo Data:

Orthoclase

Calcite

Opal

- var Opal-AN

Data

Mineral Data:

Click here to view Biotite data

Locality Data:

Click here to view Erongo Mountains, Erongo Region, Namibia

Photo Gallery

View Gallery (5 photos)

Data Identifiers

Mindat Occurrence Record ID:

387178

Long-form Identifier:

1:3:387178:2

GUID (UUID V4):

References

www.prodg.cc/johnston/erongo.htm

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Biotite from Erongo Mountains, Erongo Region, Namibia

Biotite from
Erongo Mountains, Erongo Region, Namibia