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.
Mycenaean Greece
The Bronze Age in mainland Greece is generally termed as the "Helladic period" by modern archaeologists, after "Hellas", the Greek name for Greece. This period is divided into three subperiods: The Early Helladic (EH) period (c. 2900–2000 BC) was a time of prosperity with the use of metals and a growth in technology, economy and social organization. The Middle Helladic (MH) period (c. 2000–1650 BC) faced a slower pace of development, as well as the evolution of megaron-type dwellings and cist grave burials. Finally, the Late Helladic (LH) period (c. 1650–1050 BC) roughly coincides with Mycenaean Greece.