Cryptic (geology)
The Cryptic era is an informal term for the earliest geologic evolution of the Earth and Moon. It is the oldest (informal) era of the Hadean eon, and it is commonly accepted to have begun close to 4533 million (about 4.533 billion) years ago when the Earth and Moon formed. No samples exist to date the transition between the Cryptic era and the following Basin Groups era for the Moon (see also Pre-Nectarian), though sometimes it is stated that this era ended 4150 million years ago for one or both of these bodies. Neither this time period, nor any other Hadean subdivision, has been officially recognized by the International Commission on Stratigraphy.
Historical Vedic religion
The Vedic period is held to have ended around 500 BCE. The period between 800 BCE and 200 BCE is the formative period for later Hinduism, Jainism and Buddhism. According to Michaels, the period between 500 BCE and 200 BCE is a time of "ascetic reformism". According to Michaels, the period between 200 BCE and 1100 CE is the time of "classical Hinduism", since there is "a turning point between the Vedic religion and Hindu religions". Muesse discerns a longer period of change, namely between 800 BCE and 200 BCE, which he calls the "Classical Period", when "traditional religious practices and beliefs were reassessed. The brahmins and the rituals they performed no longer enjoyed the same prestige they had in the Vedic period".