SELECT COUNT(early_chalcolithic) FROM table_23537091_1 WHERE ubaid_period_in_mesopotamia = "Second Intermediate Period of Egypt"
Ketika periode perantara kedua Mesir adalah periode ubaid di Mesopotamia berapa banyak kalkolitik awal?
CREATE TABLE table_23537091_1 (early_chalcolithic VARCHAR, ubaid_period_in_mesopotamia VARCHAR)