Ultra Thin - Drill Bits dream work Geographic Age: 66 mya -

Geographic Age: 66 mya - 160 mya

5cm  x  W: 1

the organic material is replaced by minerals

They are long lasting

possibly a mass die-off from an ash fall event or algal bloom

Ultra Thin - Drill Bits dream work Geographic Age: 66 mya -Description: Ultra thin bits are for drilling delicate, expensive or already polished material. They have a much thinner steel core, which means a narrower kerf for the hole saw. The narrower line it cuts is finer and less brutish. The grit is also a smaller particle size than standard drill bits, so there is less micro chipping upon entry. Do not use them for other purposes than listed, as standard will do just fine for most drilling, and these are