Chemists know that Mole Day, the day set aside annually to celebrate Avogradro's number (or 6.02 x 10^23), actually occurs from 6:02 AM to 6:02 PM on October 23. Publication schedules being what they are, Chemistry & Engineering News didn't go public with last year's Mole Day announcement until the next day, C&ENews Oct 24, 2011, Newscripts, but when they did, they worked in a connection to Reed College:
… take Colin Purrington’s (Reed '88, Biology) advice and use a Sakura Gelly Roll pen. In 2003, after a leaky ceiling dripped all over his lab notebook, Purrington, a former professor of evolutionary biology, got serious about ink.
“My ink was fine” after the fateful incident, Purrington says, “but the episode prompted me to think a bit more about pen choice.” So he decided to test how various writing utensils stand up to hazards that scientists might meet while experimenting: water and heat. He also tested threats chemists regularly face, such as the organic solvents methanol, ethanol, and acetone. Out of the 14 pens Purrington tested, the Sakura Gelly Roll performed best.
Contrary to the reputation that Sharpies are permanent, their ink dissolved the most readily in each of the organic solvents, as did the ink in the Bic pens tested. And if the lab is toasty, scientists should avoid fountain and Pilot pens: Their ink fades the most when exposed to heat, Purrington found.
“I was taught how important it is to keep an accurate lab notebook in college by a chemistry professor,” Purrington says of his time at Reed College, in Oregon. Purrington’s professor had been involved in forensic court cases and stressed to his students the significance of collecting accurate raw data in case they are ever challenged.
Reed chemistry profs continue to stress the importance of accurate lab notebooks written in indelible ink. If you would like to see a photograph of one of Colin's experiments with lab notebooks, various types of inks, and how they hold up to solvents and heat, visit his blog.