Dellen Crater is a roundish lake system in central Sweden near the east coast 180 miles north of Stockholm. It is about 11 miles across. The impact that formed it occurred 89.0 ± 2.7 million years ago.
Some of the impact rock from the site is called tagamite. It is a term that was introduced in 1975 to describe impact rock from the Popigai crater in Russia. Varieties of tagamites are described based on crystallinity, texture and clast content.
Some writers call these rocks by the local name “dellenites”. Others make the case for referring to all such as simply “impact melt rock”.