Mineral Evolution Database
Created and maintained by the Mineral Evolution Project in partnership with RRUFF and mindat.
Mineral locality data provided by mindat.org

Ages for Opal at Chickering Mine, Walpole, Cheshire Co., New Hampshire, USA

The cyan highlights indicate which age entries were selected as the "best" for assigning the mineral an age of 306.6Ma - 300.2Ma at this locality

Locality age

Excel ID	Max Age (Ma)	Min Age (Ma)	Dated Mineral	Minerals explicitely stated as having this age	Age applies to these Elements	Dated Locality ID	Dated Locality	Ref	Ref ID
Alexandra-0191	306.6	300.2	Muscovite			16181	Chickering Mine, Walpole, Cheshire Co., New Hampshire, USA	Bradley et al. (2016)	CM54_945