Future historians will find that the material characteristic to the era starting now is…

(4000-2001 BC was copper age, 2000-1 BC was bronze age, 1-2000 AD was iron age.)

• aluminium
• plastic
• oil
• water
• carbon dioxide
• copper again
• iron again
• silicon
• salt

Update: ramrod makes a valid point, maybe “uranium” or “hydrogen” should be added as well.

Update: appeared as Future historians will find that the material characteristic of the current era is....