Ex American collectors find. No other history or date is known about the items other than the fact that one has a sticker on it with the name James Kellor + various numbers, date 1964 ?? From the little research I did, I found that a James Kellor was part of the Glenn A Black laboratory, Indiana University. The largest with the sticker is 6cms x 4.7cms & weighs approx 139grams. NOTE: Photo’s were taken with a flash to highlight the details.