4lb chunk of obsidian, time to dig in !

[ohiocountryboy]

Rarely do I get ahold of good chunks of rock its normally arrowhead size spalls. I love making knives more though  I have less experience with large chunk. so this should be fun ( I hope). Either way it goes I'll learn from it . Any advice or tips is much  requested and appreciated.thanks.

 

[ohiocountryboy]

[ohiocountryboy]

[TRACY]

Cool! Second pic shows a ridge running all the way across the rock and I would start with removing that. I find that I forget I'm hitting glass and tend to hit hard at first.

Tracy

[Zuma]

Looks like a nice hunk. But I really can't see much, as the photos are quite dark.
I like knapping obsissian myself except for what it does to my eyes.
Please put a fan behind you or at least a good breeze. The tiny fragments
and gasses can get into your lungs and eyes very easily.
Zuma

[Stringman]

The first and third pic shows a pronounced peninsula. I would try to reduce that by a 1/2" or so. This will make it less likely to break where you don't want it too. Otherwise study it and run your ridges. Create good solid platforms that are slightly less than 90• to your flaking face and then give it a solid hit. You should be able to get a nice handful of useful flakes before focusing on your core pieces.

Have fun and post pics!