FIRE AGATE CUTTER’S GUIDE
The following article documents an approach to the cutting of Fire Agate. Refined and perfected by Ryszard Krukowski over the last 30 years, the approach maintains the natural forms of the stone, preserves solid layers of fire and finely polishes stones for perfect emphasis.
INTRODUCTION TO FIRE AGATE
Fire Agate, a relatively uncommon gemstone amongst the masses of agate and opals found in gem shows around the USA, can be a remarkably unique addition to any lapidary artist’s repertoire of cutting experience and stone collections. The stone has a very unusual formation, the result of having grown in natural volcanic pockets of trapped mineral deposits; which can make it quite a challenging stone to cut. Furthermore, Fire Agate often develops a cap of chalcedony or layers of brown which can conceal brilliant layers of fire underneath. When choosing a piece of rough to start cutting, look for indications of fire around edges of the stone or through any concealing layers. Sometimes, in the event of a large cap over a formation for example, you may have to just “cut and pray” so to speak – cut and grind away the cap, and look for fire. It might be worth to start on one side and grind off a few layers on the side to peek at layers that are underneath. Cutters often take a shortcut in the cutting process, and “window” stones – cutting away as much of a chalcedony cap as possible until they hit layers of fire, and proceed to polish the flat stones. This process, while saving time, is near impossible to predict, and often damages layers in the stone. Cutting Fire Agate can be hit or miss, but part of what makes it a very rewarding stone to cut is the fact that you can take a stone that has nothing but promise, cut away a few layers, and find a “killer” (Fire Agate Miner lingo for a REALLY great stone!)
IN THE ROUGH
With our approach to cutting Fire Agate, the natural formation is preserved as much as possible. It is a gradual process of removing chalcedony (the white crystals and milky formations which often form a cap that may conceal a really great stone) and cautious removal of agate, layer by layer, until finding the right layer of fire to polish.
Every lapidary artist finds his own style, and often his own set of tools and grinding wheels to cut Fire Agate. Fire Agate can be a tricky stone to cut, with tight grooves that require attention beyond the reach of large grinding wheels. We use a Flex-shaft (foredom) hand tool to grind into the grooves and apply fine polishing agents. Fire Agate can have complications in the cutting process, such as cracks, dead spots with discontinuation of the layers of fire, and unusual formations. Solving these problems can require getting pretty creative – you might try cutting smaller stones out of the single piece, drilling holes into the stone, even setting gold with other stones into the dead spots.
SANDED AND POLISHED
*NOTE: From experience, we have found that investing in quality tools can make a huge difference in the cutting and finishing of Fire Agate. The investment of $100 for a quick changing foredom handpiece can save you a lot of time changing bits and burs – something you will be doing constantly when cutting Fire Agate. Also, using high quality diamond wheels and bits has dramatically improved the finishing of our stones.
Cutting and polishing the stone requires a gradual change from coarser to finer wheels and polishing mediums. Recently we have been using a variety of dental sanding disks and wheels (expensive;) which are easy to control for cutting botryoidal (spherical cluster form) gemstones. Don’t hesitate on using a variety of sintered tools and dental ceramic polishing compounds, they can make the whole process of polishing and finishing a stone faster and easier. We have had remarkable success on our stones with tools from www.mtmist.org and www.vhtechnologies.com.
At this point the fire agate’s cap and brownish layers have been removed, and a layer of great fire is exposed. A flex shaft hand tool was used to work the brown out of the grooves of the stone, and various diamond wheels for broader areas. There isn’t really a developed method to the cutting process; we use whatever bit fits the job, as well as a variety of brush and sander bits.
We kept the base of the stone on as a grip during the cutting, and later flattened the base of the stone to position it correctly in a gold broach. Fire Agate has a broad range of use in jewellery, as seen in the variety of pieces in our photo galleries and on our sales pages. From mosaic and inlay work to stand alone pendants to knife handles, Fire Agate can be a remarkable flash of colour to any accessory – keychains, ipod and cell phone charms, even knife handles!
GOOD TO GOLD
Creating a jewellery setting for a piece of Fire Agate can really accent the intense colours of the stone, and can help bring out an image or object the stone might resemble. Fire Agate is a pretty hard gemstone, making it pretty versatile for all sorts of settings, mosaics, and drilling… we’ve even managed to drill out rings made entirely of Fire Agate, and set gold in grooves cut into a stone! Each piece of Fire Agate, in being unique, requires a custom setting – not some sort of generic ring mounting or setting. We often create jewellery which mimics or continues the organic forms of Fire Agate, as well as pieces which incorporate the stone into some sort of image or subject, such as flower, animals, or landscapes.
We hope our guide has given you some helpful tips and a good start towards joining the specialized group of cutters which live, breathe and dream Fire Agate. We appreciate your interest in our site and our knowledge of Fire Agate. Please email us if you have any questions for us, and we will respond ASAP. Good Luck and Happy Cutting!!!
Written by: Ryszard Krukowski I + Ryszard Krukowski II