What type of materials, like Ramon's diary pages, tended to survive re-entry better than the biological remains of the crew?

Dense personal items with lower surface-area-to-mass ratios

A significant observation made during the recovery was the contrast in survivability between the soft biological matter of the crew and certain personal effects. While human tissue could not effectively dissipate the extreme kinetic and thermal energy and thus vaporized or shattered under shear stress, denser, non-biological materials often fared better. Items like paper documents or items protected within solid casings survived because materials with a lower surface-area-to-mass ratio tended to shed heat more effectively or were physically shielded within protective structures, allowing them to withstand the assault that destroyed the crew compartment.