The gotcha is that the types of Marble you can attune to is limited by your perception. For the more exotic types of Marble, you'll need a boost from eating Perception Food. Grill Carrots will do nicely for the initial four Marbles.
When you select ESC > Skills > Prospect for <your Marble>, you'll get one of three results.
The largest possible search DIAMETER is a relative (0,0) to (31,31) which is 45.25 coordinates. It's much easier if you simply use 30 coordinates of separation, a relative (0,0) to (30,30). You can go faster that way, as the search will still work just fine if you're not quite precisely on target. If you stagger alternate sweeps, the search circles will fit nicely together. The recommended offset is X + 35 and Y+15. The precise X value would be X = 31*((1+sqrt(2)))/2 = 37.4, so offsetting by only 35 coordinates leaves you with a couple coordinates of overlap for fighting with the terrain.
Follow the recommended 60 coordinate zigzag pattern until you find a "Two Slate Break".Some marbles, Oyster Shell Marble in particular, are very common, with a distribution of about 1/1024 of all cells containing OSM. In other words, it's very likely that you will get a two break on your first try.
You and your partner should be attuned to DIFFERENT Marbles. You and your Partner should aternately move 60 coordinates but you should BOTH Prospect for Marble after EACH move during the initial zigzag search.
Keeping one partner in place while the other moves 60 coords has the advantage that the stationary partner can be a reference if the moving partner forgets where he is going. But if you're both confident you won't forget your spots, it can be more time-efficient if you both simultaneously move 30 instead. -Numaris
If there already a Quarry of your type in the area, simply ensure that your partner is between you and the existing Quarry, and you'll never see it.
Note that you're "wasting" one coordinate because you're only searching a diameter of 30 rather than 31. The advantage is that you can move with minimal coordination, and can efficiently cover a lot of territory. By staggering passes, you can fill in the spaces between the circle, covering the gaps rather than doing a redundant check.
Double F8 (north facing cartography) is the best view. Use /clockloc and drag the popup right next to your avatar.
The kind of terrain (except water) doesn't matter for the Marble, but prospecting in mountainous terrain can be a pain.
When either of you get a "Two Slate Break", go the next section and isolate the related Quarry.
You'll do most of the running around and all of the Prospecting for <your Marble>. The isolation pattern begins by moving your partner halfway towards you. This establishes the rotated SIDE of the next inscribed quartering square. If your partner drops a tabpole each time they center, it creates a very help track of the spiral search pattern.
If you enter your partner's coordinates into the map, the program will adjust all of the numbers so that you can easily follow the action. You can print out the map if you wish, but printed Excel graphics aren't particularly accurate.
After your partner moves, and before you break any more slate, you'll make a move that's tricky and counter-intuitive. You will move at 90 degrees to your partner's direction of travel, and half again further (sqrt(2)). Your partner is moving to the center of the new smaller search square, but you're moving to the rotated corner of the new search square.
The key concept is that a "Two Slate Break" always allows you to reduce the size of the search circle by half. You can therefore isolate your Quarry by prospecting closer and closer to the actual center. We've only shown the successful "Two Slate Breaks". The unsuccessful "One Slate Breaks" were the the same distance from the Partner, but in the wrong direction.
Each "Two Slate Break" circle is quartered by using smaller circles that include the center of the "Two Slate Break" circle and the two corners of an inscribed square. The area of the search circle (and the inscribed square) reduces by half with each iteration. The circle that's used to "quarter" the larger circle actually covers 34% of the larger circle, so your search efficiency is 34%, 34%, 16%, 16%. Note that the value of fourth search is purely psychological, but it's sure satifying to nail it.
When you find a Two Slate Break where the locations for you and your partner differ by only one coordinate, in one direction (NSEW), move your partner to the midpoint between the intersections. That's the location of your Marble.
The search distances are 30 diagonal, 30 adjacent, 16 diagonal, 16 adjacent, 8 diagonal, 8 adjacent, 4 diagonal, 4 adjacent, 2 diagonal, 2 adjacent, 1 diagonal, 1 adjacent, 0.5 adjacent (with your partner at a edge midpoint and you in the adjacent cell midpoints or intersections). The value of the last 1/2 distance search on all four sides of your partner is purely phychological, but it's certainly worth the extra 8 slate.
For this snapshot, we found the exact intersections for the local cells by finding the spot where a single diagonal step took us from (0,0) to (1,1), and we then dropped a tadpole at the (1,1) point.
From a Geometry point of view, what we're actually doing is rotating an inscribed square by 45 degrees for each iteration, and always searching a diagonal.
For those of you who are fond of Geometry, assuming a radius of 1 for the larger circle,
Isolating the Quarry is more difficult. We'll need 11 iterations to get from 1414 cells to 1 Quarry. Because of the area covered by the quartering circles, 100 quartering trials would need
On average, finding a Quarry using the recommended procedures will therefore take 1 Slate per 35x30 square, depending on the rarity of a particular Marble, to find a Two Slate Break, plus 34.5 more Slate to isolate the Quarry.
We've ignored the fact that you are BOTH prospecting. That's just quicker, not more efficient. If you are averaging less than 38.5 Slate per Quarry, let's talk.
Here's the search data for an OSM Quarry that was built during Tale 2, Year 3, Akhet III-5 using 36 Slate. The previous Oyster Shell Marble Quarry was built the day before at 1301 2424. We were prospecting from south to north, so read the data from the bottom up.
Move | X = | Y = | Result |
BUILD | 1292 | 2476 | QUARRY |
verify 1C | 1293 | 2476 | TWO |
verify 1C | 1291 | 2476 | TWO |
verify 1C | 1292 | 2475 | TWO |
verify 1C | 1292 | 2477 | TWO |
NONE | 1292 | 2476 | |
1D | 1293 | 2477 | TWO |
HALF | 1292 | 2476 | |
2C | 1292 | 2477 | TWO |
HALF | 1292 | 2475 | |
2D | 1293 | 2476 | TWO |
2D | 1289 | 2472 | ONE |
2D | 1289 | 2476 | ONE |
2D | 1293 | 2472 | ONE |
HALF | 1291 | 2474 | |
4C | 1291 | 2472 | TWO |
HALF | 1291 | 2476 | |
4D | 1289 | 2474 | TWO |
HALF | 1293 | 2478 | verify |
8C | 1289 | 2478 | TWO |
8C | 1297 | 2486 | ONE |
8C | 1297 | 2470 | ONE |
HALF | 1297 | 2478 | |
8D | 1301 | 2474 | TWO |
HALF | 1293 | 2481 | |
16C | 1293 | 2473 | TWO |
16C | 1293 | 2505 | ONE |
HALF | 1293 | 2489 | |
16D | 1301 | 2497 | TWO |
HALF | 1285 | 2481 | |
32C | 1285 | 2497 | TWO |
HALF | 1285 | 2465 | |
ZIGZAG | 1270 | 2480 | TWO |
PARTNER | 1300 | 2450 |
We've entered the Quarry coordinates on the map, so you can also follow the action graphically.
The initial Two Slate Break was outside of the search square, nearly to the edge of the search circle. The important concept for following the action is that each midpoint (Half point) is quaranteed to be somewhere in a smaller search circle. We then quarter that circle so we can make the next search circle even smaller. We're cutting the possible quarry locations in half each time we get a successful "Two Slate Break".
Built: outside (projects menu)
Skill/Tech required: Rocks of the Ages
If you wish to practice, there is a known Oyster Shell Marble deposit in Seven Lakes, just west of the UThought at 1248, 2377.5, just across the road from a cluster of thorns, and too close to the road to be able to build a quarry. If you have access to Microsoft Excel, you can download the attached Prospecting_2005J14.xls spreadsheet and set the coodinates for your own searches. | ![]() |
Name | Creator | Date | Size | Description |
---|---|---|---|---|
OSM_Practice_Site.jpg | MarvL | June 25, 2006 3:11 pm | 15121 | OSM that's too close to the road to actually build a quarry |
Prospecting_2005J14.xls | MarvL | June 25, 2006 1:22 pm | 67584 | Prospecting Temple (Microsoft Excel) |
Quarry_Isolation.gif | MarvL | June 25, 2006 1:24 pm | 32338 | Quarry isolation by quartering the circle |
Spiral.gif | MarvL | June 25, 2006 1:25 pm | 9095 | The path followed by the centered partner, and the slate breaker |
Staggered.gif | MarvL | June 25, 2006 1:27 pm | 38538 | The recommend search pattern, until you find a two slate break |
Tadpoles.gif | MarvL | June 25, 2006 1:28 pm | 83717 | The Tadpoles are in the low-numbered corner of successive center cells |
Vein.gif | MarvL | June 25, 2006 1:29 pm | 153028 | Here's how the Quarry lines up when you were standing on the edge midpoint |