In the American catastrophe which took place simultaneously with the Palestinian crucifixion, there was awful d. It lasted for "three days" and was so thick that they "could feel the vapor of d." The density of this vapor was phenomenal because it says "there could be no light because of the d.; neither candles, neither torches; neither could there be fire kindled with their fine and exceeding dry wood, so that there could not be any light at all." 3 Ne. iv: 17-21. In Judea there was d. "over the whole land" from the sixth to the ninth hour. Which latter occurrence is confirmed by the pagan Phlegon of Trallium who lived about A. D. 150 and describes such a d. and accompanying "earthquake" as taking place in the 202 Olympiad, year 4, corresponding with the 33rd (crucifixion) year of the Christian era. See Mk. 15:38.
Also Lambert's Notes on Ingersoll p.148. Tangible darkness was one of the plagues visited upon ancient Egypt. Ex. 10:21.