The Mineral Evolution database is currently under development.
The goal of this page is to present localities at which the mineral is found, and estimates of the oldest possible geologic age of the minerals at these localities.
Locality Name:Goonbarrow China Clay Pit, Bugle, Treverbyn, Cornwall, England, UKOldest recorded age at locality: 313Youngest recorded age at locality: 253.1mindat Locality ID: 1189mindat URL:http://www.mindat.org/loc-1189.htmlTectonic Settings: Total number of sublocalities beneath "Goonbarrow China Clay Pit, Bugle, Treverbyn, Cornwall, England, UK": 1Total number of bottom-level sublocalities: 2Latitude: 50°23'17"NLongitude: 4°48'14"WDecimal Degree (lat, lon): 50.388055555556,-4.8038888888889
A
This mineral is Anthropogenic.
G
This mineral is directly dated.
B
This mineral is reported as having this age.
Y
This mineral is using an age reported as an element mineralization period.
O
This mineral is using an age calculated from all data at the locality.
R
The age displayed for this mineral originates from a different, non-child locality.
P
The age displayed for this mineral is the range of ages for this mineral at all of this locality's children.
This mineral's age has not yet been recorded.
This Mineral list contains entries from this locality, including sub-localities. Minerals in bold are reported by mindat.org as occurring directly at this locality, and do not occur at any children (sublocalities) of this locality.Elements at this locality, including sub-localities: AlBeCaCuFFeHKOPSSiSnZnElements from minerals reported directly at this locality: Al Be Ca Cu F Fe H K O P S Si Sn Zn Structural Groups for minerals in this locality:
Metafelsite dikes which conspicuously crosscut sheeted veins but which are themselves hydrothermally metamorphosed to a quartz-muscovite-kaolinite assemblages.
Since evidence suggests that secondary muscovite and kaolinitc in metafelsite dikes and kaolinized granite are significantly cogenetic, these data and the geologic relationships indicate that sheeted vein mineralization, greisenization, and kaolinization were simultaneous processes which occurred in the time interval between granite crystallization at 301±12 m.y. (whole-rock Rb/Sr isochron for the St. Austell granite) and cooling below a mica closure temperature of '~250oC at 273.6±1.1 m.y. (pooled K-Ar age based on 50 acceptable values).
Since evidence suggests that secondary muscovite and kaolinitc in metafelsite dikes and kaolinized granite are significantly cogenetic, these data and the geologic relationships indicate that sheeted vein mineralization, greisenization, and kaolinization were simultaneous processes which occurred in the time interval between granite crystallization at 301±12 m.y. (whole-rock Rb/Sr isochron for the St. Austell granite) and cooling below a mica closure temperature of '~250oC at 273.6±1.1 m.y. (pooled K-Ar age based on 50 acceptable values).
These dates are consistent with an estimate of 280 ± 2 m.y., based on five Rb/Sr age determinations, for the time of felsite dike intrusion and sheeted vein mineralization.