DDD Posted October 29, 2009 Share Posted October 29, 2009 (edited) I have gone through raw matrix before and found the beetles as you see them at a show though they are generally given a coating or two of Butvar and then given a slight polish while the matrix is dulled down a little for contrast. I prepped a few years ago but "tar bugs" are not available in the numbers they once were. Back in the late 80's and early 90's, at least a couple of guys were digging and prepping them by the flat. It's messy, time-consuming work and got to the point that selling them at $2 each by the flat wasn't worth the trouble. All the beetles I've seen come from Kern County sites. siteseer, I've recently purchased a number of La Brea specimens from veomega at Devonian Depot. The last three I just received today are tar bugs, one of which has an additional beetle or two still mostly in the matrix (i.e., not prepped out). Can you elaborate for me on the best techniques to get these additional beetles exposed and cleaned up? Also, if anyone knows more details of the present state of 'visitability' of the pit(s) in McKittrick, CA where all these specimens were from I would be very interested in visiting there myself. I'm in the LA/Edwards/Mojave area often enough that a trip to McKittrick would be an easy side trip. Dan Edited October 30, 2009 by DDD Link to comment Share on other sites More sharing options...
siteseer Posted October 30, 2009 Share Posted October 30, 2009 siteseer, I've recently purchased a number of La Brea specimens from veomega at Devonian Depot. The last three I just received today are tar bugs, one of which has an additional beetle or two still mostly in the matrix (i.e., not prepped out). Can you elaborate for me on the best techniques to get these additional beetles exposed and cleaned up? Dan Dan, You need to carefully pick away at the matrix (dental tool), using acetone to soften it up (model kit paint brush), working one small spot at a time. Make sure you do this in a well-ventilated area - either outside or inside near a door or window with a fan going. The insects are fragile. Generally the legs are gone, but sometimes, a few are still tucked underneath. The wing covers are fairly resilient (bending but not breaking like plastic) but they will separate from the body if you aren't careful. After you have exposed as much of the bug as you want, make sure it's clean and then give it a coating of Butvar mixed with acetone (at least one part Butvar per three parts acetone - sort of the viscosity of superglue) and the surrounding matrix as well or it will start "shedding" tar which gets everywhere if you're not careful. If you use too much Butvar, the bug will cloud up to a milky color. Wipe it gently with a little acetone. As an extra note, if you find any small bones or teeth in the matrix, be very careful cleaning around them as well. They are also quite fragile (bending/fragmenting very easily) - not as solid as they look since have been permeated with tar for thousands of years. The beetles can be found in the older and younger tar layers but seem more common in the younger ones. The tar layers range from around 30,000 to about 9,000 years old. If you are finding mostly bird and rodent bones, you are probably in the youngest layers. You won't find any horse, camel, Smilodon, nor dire wolf in that - maybe the occasional coyote tooth or toe bone. I don't know what the current accessibility is for McKittrick. One site was right along the road (Hwy 33?). You had to get permission to collect the known Maricopa site but people did well there in the 70's. You had to be lucky because the material tended to be found in pockets. Link to comment Share on other sites More sharing options...
DDD Posted October 30, 2009 Share Posted October 30, 2009 Very helpful - thanks, siteseer! Dan Link to comment Share on other sites More sharing options...
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