An anonymous Broken Hill prospector pulled a 1,218-gram gold nugget from the red dirt of Mount Stuart station near Tibooburra in far northwestern New South Wales in mid-October. Testing showed the quartz-flecked piece, which he nicknamed the Tibooburra Spud, contains about 940 grams of pure gold. At current spot prices it is worth $150,000 to $160,000, and the finder believes a collector could pay up to $200,000 for the intact specimen. The man, who has...

UC Berkeley mathematics professor Richard Borcherds, a 1998 Fields Medal winner, has stopped grading student homework for correctness. He now awards credit mainly for whether assignments are turned in on time, after concluding that artificial intelligence tools have made traditional marking unreliable. Borcherds, 66, told the Daily Californian in a sit-down interview published October 23 that student use of AI for homework has become widespread. He said grading answers for accuracy creates a strong incentive...