That 18" inch saw has cut lots of blue forest material! Here you can see that this piece is clamped in with the assistance of wood wedges. Cutting ought to always be the first step and note that the algae is still present on the exterior to help protect the piece during both clamping in the saw vise and the vibration during cutting.
I always use diesel oil as a cutting lubricant in my saws, so it makes sense that scrubbing with dawn dish soap and hot water is the first step in removing the bulk of that oil after cutting.
The pieces are then covered completely in kitty litter and left for two days to continue to absorb the diesel. Any kind of absorbent substrate can be used, such as dry sweep, however kitty litter is the most economical.
Baking is the final step for removing the last traces of oil. This step is very crucial, as there are small cracks and pours in your specimen that no amount of washing or sanding can get to. I use an old gas stove which I keep covered outside when not being used. Baking at 300 - 325 degrees for 3-4 hours is sufficient to burn off the remainder of diesel on your Blue Forest wood. It is a good idea to leave the oven door cracked open a little during baking to allow the diesel smoke to exit easily and also, this helps you easily gauge that when there is little or no smoke that the process is complete.
Now the fun begins! Ok, its been three days and your blue forest wood is cut and finally cleaned of saw lubricant. Time to begin working on that calcite and outer layer of algae. Soaking your pieces in dilute Muriatic acid (HCI) will remove the calcite and also soften and partially break down the layers of exterior algae making it easier to remove. Always wear safety glasses and rubber gloves when working with Muriatic acid. Also work outdoors or in a ventilated area as the fumes can be irritating.
NEUTRALIZE ACID WITH BAKING SODA! Once all of the calcite is etched away with the acid and the algae is down to a manageable level it is crucial to neutralize the acid left behind on your blue forest wood. A strong soaking in baking soda is the best way of accomplishing this. Two or three hours of soaking is usually enough to neutralize your piece but be sure to check the baking soda bath afterwords for any missing pieces of chalcedony that may have fallen off during this soaking.
After a long soaking in muriatic acid a large cavity is left behind. The calcite that used to occupy this space has been dissolvd away, exposing a lovely botryoidal chalcedony lining. The outer algae on this piece is seen here to be getting thinner after the acid treatment and the "finished" limb can be visualized once all of that algae has been removed.
After acid etching it is not uncommon to have pieces of that lovely chalcedony break away from the specimen. And so it is our responsibility as preparers to do our very best to restore any missing segments that we can find. Here, it can be seen that a segment of chalcedony has fallen away from the left center of the limb. The detached piece can be seen in the box with others that I have recovered from the acid bath.
Here the close-up shows the area has been cleaned of debris and is prepared for restoration.
Cyanoacrylate is applied with a fine applicator tip to re-attach the segment. It can never be stated enough that restoration and repair on any specimen of scientific or aesthetic value is always of greatest importance and your specimen is no exception.
OK, so re-attaching small segments of delicate material has been addressed but the removal of large quantities of fossil algae is perhaps the biggest challenge for the preparer of Blue Forest wood. It may be surprising to some that an angle grinder can be your best friend when accomplishing such daunting tasks. This machine will make quick work of even the thickest algae layers.
As the algae thins and you get closer to that chalcedony layer, smaller tools can be employed. This flex-shaft dremel tool with a diamond bur does a fair job but a pneumatic air scribe really works best.
Rarely, a hammer and chisel are used - but care and caution must be exercised, as jarring blows might open fractures or cause other unforeseen damage to your specimen.
O.K., so you may think that glueing is somehow wrong? Or possibly that it's considered "unnatural"? Or maybe that a specimen that has been glued is somehow worth less than one that has not? Nothing could be further from the truth and when it comes to sound natural history preservation, nothing is more important than gluing. It is glue that holds millions of natural history collectibles together around the globe and throughout our worlds museums. Fossils, pottery, shells, minerals, skeletons and even entire dioramas. All are held together by glue. Glue provides stability and strength to a specimen. Glue adds infinite years to otherwise fragile objects which allows us to study, appreciate and enjoy something that might have otherwise crumbled into dust. For blue forest wood I use either starbond or paleobond and it is really handy to add fine applicator tips to the glue bottle so that fracture lines can be followed easily and the glue used effeciantly. You can get applicator tips at any model/hobby supply store.
After countless hours of work, a batch of Blue Forest wood is finally ready for polishing. You can see here that I have left some minor algae attached to a few of the specimens and there are glue lines on one of the pieces at upper right indicating that there were fractures in the cut face that needed to be sealed before polishing. Again, I would like to reenforce the concept that preservation is the main goal when preparing your Blue Forest wood and steps such as sealing fractures will not only strengthen your specimen in the end but also greatly improve its durability and appearance.
FINALLY IT'S TIME FOR A POLISH!
Now that all the steps have been taken to prepare the outside of your blue forest piece, it's finally time to give it a beautiful, glassy polish!
Personal protective equipment to be worn:
Large amounts of fine, particulate dust can be generated during the sanding and polishing process and taking steps to insure your own safety before this All sanding/polishing steps below were performed dry. It is of greatest importance to wear the proper PPE (personal protective equipment) while performing this work. It is also strongly advised to run a vacuum system or shop vac during any dry sanding work as well as a use a properly fitted respirator.
The first step in polishing is to grind flat any nubs or saw marks. These are the result of your saw blade's beginning cut and finishing cut.
On to a belt sander with 36 grit silicon carbide paper. This step will help flatten the surface as well as remove any glues that were applied to seal fractures.
A bull Wheel is the "star of the show" during the polishing process of Blue Forest wood or any other stone for that matter. The pricision surface that can be achieved by this machine can't be matched. The 12" disc is backed with carpet padding to which 60 grit silicon carbide sand paper has been glued.
The other end of the Bull Wheel unit has a 12" expansion drum with 400 grit silicon carbide sand paper. This step produces the prepolished surface.
The final polish is accomplished using an arbor fitted with a 8" rubber backed wheel and covered with sturdy canvas. The canvas is charged with a paste of Tripoli and the stone is periodically brushed with more as it is worked to a mirror finish. Though Tripoli is considered a prepolish in the trade, the torque and RPM's applied to the stone with this machine will generate a superior mirror polish that is unequaled anywhere today.
The final step: Bleaching? Yes, that's right. A large quantity of Blue Forest wood is jet black when collected, and must actually be bleached in order to bring to light the beautiful wood grain that it is so well known for. The process is a simple one and only requires you to soak the polished face of your specimen from 20 minutes to several hours (depending on the individual piece). After soaking countless specimens I have learned that not every piece will lighten and that some take longer to lighten than others. Practice experimentation and patience and you will nearly always have great results.
Where is The Blue Forest?