Listen up, chumps! Enchanted forests are real! If you're hankering for a lively day of hounding within driving distance of the Oregon coast, but tired of beach combing, I highly suggest checking out Tillamook State Forest. In addition to the usual petrified wood, pyrite (I will make you mine one of these days!), agate, and jasper, there is a sweetness to be found by the name of augite. If you want to leave your lips tingling, while also repelling anyone vaguely interested in what you're saying, I suggest the following phrase: "Check out these calcium sodium magnesium iron aluminum silicate crystals!" I know- doesn't it just roll off the tongue? These little black gemy babes are the perfect hounding for (well supervised) kids and (childlike) adults. Tillamook State Forest has three locations listed for hounding in my field guide. The end of September signified the last expedition I was able to cram into my end-of-season clean up in Astoria, OR [Figure 1]. For this occasion, Janelle, a gifted field biologist for the Oregon State Department of Fish & Wildlife, accompanied me down the Oregon coast to Jones Creek and Cedar Butte.
Jones Creek was a limited success, the only photo I snapped was of the beautifully exposed gravel beds of Jones Creek [Figure 2]. Open and waiting to be picked, we barely toiled to keep our feet dry in the cooling weather. This visit was rife with some kind of blue agate material -currently in my tumbler- along with white agate, zeolites, and evidence of pyrite. It was late in the season to be finding a lot of goodies left over at Jones Creek, and our best samples came from the furthest part of the creek from the site listed. Not at all surprising, considering that folks will, rightfully, thoroughly preen the starting locations cited in guides before moving up or down stream. If we really wanted to fill our bucket, I could have driven another mile or two up the gravel road and begun there. For the sake of hitting two sites in one day, I took the quick-and-dirty tactic and we plopped ourselves precisely at the coordinates listed in A Falcon Guide: Rockhounding Oregon.
Allow me to qualify "evidence of pyrite," before we delve too deeply, here. Pyrite is one thing I have yet to cross off my list, and the red streaks creasing the eroding banks of Jones Creek were indicative of iron-laden clay. Just the kind of environment where you would expect to find iron pyrite peeking out. These signs, and the well over-picked creek bed, sang seductive promises of pyrite cubes hidden in the erosion piles and gravel. I know that sexy little minx, pyrite, was definitely there at some point this year, but a song is not a promise. To reiterate, I may not always find what I'm looking for, but I never go home empty handed. What is this blue stuff with streaks of mineral through it that I did fill my pockets with? Who knows! One thing is clear to me: it's a hot rock, and so far it's polishing up nicely. Pyrite failures and indecisive mineral identification aside, now I know where to start next time I hound Jones Creek. Even without the lust for nature booty, it's a lovely area, and the fall view was well worth the drive.
Next up on our trek through Tillamook was the famous Cedar Butte. The Cedar Butte Trailhead is just across the Wilson River, and starts about five miles up the timber road marked with its name. The trail to the dig site is pleasantly maintained and aromatic with forest life. Most unlike other sites I venture to that require digging, the substrate at Cedar Butte is crazy soft. Hillside erosion is a blessing for rockhounds, providing rich tailing piles and tracks of exposed material for picking [Figure 3]. Augite is a pleasure in the PNW, so filling our sample bags with decent specimens without breaking a sweat still boggle my mind exhilarated me. Hopefully, it exhilarated Janelle as well...'it's always difficult to tell when I'm being humored in such stimulating circumstances. Especially when a site is so renowned. "Legend tells [augite is] only found in two places. The Tillamook coastal mountains and Doty hills Adna, WA [Bill Sprinkle, Facebook comment]."
It. Was. Glorious. My natural inclination is now to woo you into rock-bloggy bliss with a titillating tale of rockhounding wonderment; but sadly, the journey to Cedar Butte wasn’t my usual tumultuous expedition into the wild unknown, pickax in hand. That's how accessible it is. Follow the signs, drive carefully, watch for timber trucks & downward traffic, end with a short jaunt through the woods to the hillside dig site, and you're golden. Given that the goods collected were far more interesting than the journey to either site in this enchanted forest, it's time for a little mineralogical dirty talk.
Come with me, and lettuce* take a sojourn down the lovely course of what the heck composes these mysterious black beauties. Indeed a calcium sodium magnesium iron aluminum silicate crystal, augite enters the floor stage-left (because why not) dressed in dark, solid colors and creased straight lines. It has a classic, old-school appearance sure to outlive the times. I totally dug their sense of style before I actually dug for them. Explanation: There is only one picture of them in my field guide and upon seeing it, I knew it was necessary for my sanity* to at least experience them in person, if not collect them. As with all natural beauty, there is some dissension among mineralogists who hesitate to share my praise -don’t hold your breath- of our elegant friend. I was so off-put by one entry online, that I decided to give you the bad news first, which is that these schmucks at www.Minerals.net/MineralImages/A.aspx claim, “Augite usually occurs in dull crystals that are ugly and uninteresting.” Someone needs an attitude check. After all, the only real qualities to be measured by society (if any, and in this case, according to Plato) are Wisdom, Courage, Moderation, and Justice. None of which can be inferred simply by coloration [I do not have a reference for this, somehow between the audio lectures and books, I lost the original source… let’s say it’s almost certainly from one of the Republics]. Societal criticisms aside, Minerals.net did provide the most succinct depiction of augite mineralogically:
“Augite is isomorphous* with the minerals Diopside and Hedenbergite. It is an intermediary member between these minerals, forming a series, but contains additional sodium and aluminum within its chemical structure. Strictly speaking, because of the variables in its chemical structure, augite is really more of a group then a single mineral, but it is still classified a single mineral species by the International Mineralogical Association.
(Here is where it gets good) Augite is an important rock-forming mineral, and large crystals are fairly common. It is the most widespread member of the pyroxene* group, and it frequently alters into many other minerals, including Hornblende, Chlorite, and Epidote. When altered to Actinolite, it is often called Uralite….Occasionally, it is found in large lustrous crystals which are sought after by mineral collectors. The name augite is derived from the Greek word (like so many ancient and beautiful things) augites, ‘brightness’, in reference to the bright luster this mineral occasionally exhibits.”
Couple things: Do you see what I mean about the sass? Whoever wrote this index entry has a serious chip on their shoulder about the speciation of my sexy little calcium sodium magnesium iron aluminum silicate babes [Figure 4]. Sheesh, and I thought ornithologists were touchy (all my bird folks know what I’m talking about). Although, knowing that rocks have species is just a treasure all its own; so, I guess my threshold for satisfactory rock taxonomy is dead on arrival. Lucky for me, "Oregon, in particular, is fortunate to be home to some of the best specimens of augite in the country, some of which are perfectly crystallized and exemplify the mineral [Rocks & Minerals of Washington and Oregon]." This entry goes on to say that Cedar Butte is one of the most famous localities for collecting augite in the United States. Take that, snotty mineral internet person!
I suppose, after you venture into the enchanted forest to find these you could tumble them, as my Falcon Guide suggests. About half of the ones you will find at Cedar Butte are stable enough to polish, if you want shiny, black, slightly angular stones. Personally, I think the peanut butter jar I filled with good and not-so-good specimens is much more attractive as it is than with smooth black pebbles. At some point, I will make it down to the Glass Butte and get me some of that delicious obsidian I see everyone experimenting with, and I will have all the black pebbles I can stand. That's a massive over simplification, actually. I understand that tumbling obsidian is damn near a kung fu of specificity. As I discussed in Tears & Spears, it's so soft that the tumbling process needs to be overly sensitive to get the desired mirror shine (if they don't disintegrate) and striking that balance can take years. In any case, this rock rat hopes to heaven that you can appreciate these babies for what they are: smallish, well-dressed, and magical. If not, then a stroll through the enchanted Tillamook State Forest might just convince you!
*Lettuce = Let us: this joke is never not funny. You're welcome.
*Sanity: A term used loosely in this blog.
*Isomorphous: Describing two or more minerals that have the same crystal form (meaning that the molecular arrangement is identical) but their specific elements are different. Isomorphous minerals contain different elements arranged in the same arrangement and number, such as Calcite and Siderite, where the calcium and iron are interchangeable [http://www.minerals.net/mineral_glossary/isomorphous.aspx]
*Pyroxene group: A group of hard, dark, rock-building minerals that make up many dark-colored rocks like basalt or gabbro [Rocka & Minerals of Washington and Oregon]