Very, Very Old House, Built About 1550, Renovated About 1680

OK, wish me luck... I've finally begun to search an old house that I've been trying to get into for about a year... "Don Hernan" (pseudonym for the old man who's the owner) finally felt comfortable enough to let me in to search the property. It's thought to be one of the oldest buildings in this colonial city, built around 1550 as a viceroy's palace, yet the roof and plastering are newer, dating to around 1680. There has been no apparent modernization other than to add indoor plumbing (one bathroom) about thirty years ago. Unfortunately, the entire interior floor area (both all rooms indoors and outside around the central courtyard) are all covered with modern concrete dating to between around 1890 to 1930.

I was unable to attach photos, but if I can figure out how to downsize them I will update later. 

Don Hernan says he's agreeable to breaking up the floor if I think there's treasure beneath, and I plan to dig all targets. He's been trying to sell the house for awhile and move into an apartment and I'm guessing that he wants to satisfy his curiosity about whether his lifelong home contains any hidden treasure. There is anecdotal evidence that a huaca was discovered around forty years ago by workmen repairing a back wall, and the proceeds from that reported treasure were said to have been used by the family for the construction of a modern building on a nearby site.

I plan to spend as much time as it takes, or as long as he'll let me stay; I've budgeted a couple hours a day for a whole month. A part of the house was searched with a metal detector about fifteen years ago, and several relics were discovered, including a couple pieces of silverware, yet no gold. Even though I would have preferred to begin by searching around the old courtyard, because "ghosts" have told Don Hernan that the treasure is to be found below the floor of a certain side gallery in the building, so to humor him that's where I've begun the search; still, I'm trying to keep an open mind and I try to have in my mind a picture of how this place may have looked three or four hundred years ago. To begin, I've searched the entire floor of this gallery twice with a Garrett 2500 (I also have a SeaHunter, which may be better for the salt here) and have marked the target locations on the concrete floor using paint.

Tomorrow I'll go back over everything with either/both the 2500 and the SeaHunter. I also have the two-box setup for the 2500 so I'll probably try that also. Then I'll have my workman start breaking up the concrete floor over the marked target areas, using a compressor and pneumatic hammer and hoping to avoid damaging the house through excessive vibration. Of course, we'll also need to fill in the holes and top with new concrete, plus dispose of all the dirt which won't fit back into its hole... After finishing this first area (one of two side galleries) I'll move to the courtyard area. I'm hoping to learn as I go, and by the time I finish the house completely the first time in a few weeks, including walls and ceilings, if I still have access I'll come back again. This is all assuming that Don Hernan doesn't become prematurely discouraged if we only discover iron at first.

Any thoughts about how to best focus on finding the goodies (if they exist), yet without breaking up and digging under the entire concrete floor? Thanks!

EF

Definitely check the grounds outside if you get the chance (especially looking for old wells, as that is where a lot of treasure got dumped when pirates were about.)  Good luck!

[John 3:16]

edflower, this sounds like a really amazing place to detect.  It is exciting just to read the story.   I did not know there were buildings that old, still standing in the Americas.   

Does the concrete have steel reinforcing bars in it?  Just curious.

Good luck, I hope you share some photos with us! 

Before I ripped up the hacienda, I'd check the grounds!   

Thanks for the good suggestions. The building is a colonial-style "townhouse" so it's basically four high walls built around a central courtyard. It's located only about a hundred meters from the beach, built on the supposed site where the first encampments were. On the one hand, I want to "dig all targets." Yet at the same time I believe that, at some point during the search if I've broken up numerous small holes in the man's floor without finding something interesting then he may lose interest in proceeding further. So, I want to be as focused yet still as thorough as possible.

I have pictures of the property, and I'll work on downsizing them for posting. Of course, I'll also take pictures of progress as the digging begins.

EF

I guess you have to figure out ahead of time what kind of treasure would be buried, and what kind of container (if any) houses it.  This could help you narrow down the signals worth digging for.  If that modern concrete has reinforcing bars in it, that's a problem. 

Since you are looking for 16th C. Spanish treasure, it's not going to be a mason jar with a zinc lid   

If it's in a box, perhaps an iron-bound chest?   I'd go over that area with your two-box setup.

I don't know anything about cache hunting, just drawing on experience of digging up big hunks of iron and crushed beer cans.  A couple of the large objects I dug up could just as easily have been caches.   

One object I dug the other day (still in the ground) was a nice signal, but proved to be a section of cast-iron pipe almost two feet down.

I once dug up a tin-plated copper pot or basin of some type, all mashed up, buried more than 2 feet deep, down beneath some rocks.  It gave a nice "coin" signal on my detector.  It took me over an hour to pry up the densely packed rocks.   

If you have a signal, and it seems like a nice coin-type signal, but your two-box will detect it, then it's probably a big object buried deeply.

Of course there is great possibility for the isolated drops of Spanish coinage.   At least you know, if you break through that concrete, that it won't be a Budweiser can. 

Thanks to all for the good insight. OK, we've dug three holes over areas in the floor which gave promising, repeatable signals. It turns out that the upper layer of floor is made of modern concrete, yet without rebars or other significant iron-- no problem there. Instead, the problem is that under the thankfully-thin modern concrete, there's a layer of bricks in place from the previous flooring dating back a couple hundred years, and in places that brick is overlaid with rubble of fired-clay Spanish roofing tiles, which are "hot" and therefore being detected by the Garrett even when using discrimination.

 So, my initial surveys made by running the detector over the existing concrete floor had shown an "interesting pattern" which looked like a debris field in a circular pattern; however, it now seems that at least some of these signals (three out of three holes dug so far) have yielded pieces of old "hot" tiles fallen or discarded from the previous roof, but no other metal thus far. I've dug the three holes down past the bricks to a depth of about eighteen inches below the surface of the modern concrete, and put the Garrett detector coil down into the dug holes, but no signals below the "hot" tiles.

Digging and sifting the contents of the three holes yielded animal bones and fragments from Spanish-type ollas which lead me to believe it was formerly the site of a trash pit at some point in time. Among the bone fragments and early masonry fragments found below, I came across another of what appears to be a piece of boar-tusk, or perhaps a similar horn-bone material. I'll try to post some photos.

Since I believe these annoying pieces of roofing tiles may be spread out randomly around the property, i.e., fragments from this same batch of fired-clay tiles with "hot" properties may be located elsewhere under the floors of the property, I'm wondering if there would be an easy way to "notch out" only the signals from these tiles, or perhaps some other way of avoiding breaking unnecessary holes through the concrete only to find more tiles.

Any thoughts?

Thanks for your time and insight,

EF

This roofing tile problem is similar to the "Gravel Driveway" problem I have been noticing lately.  The fired clay, especially with iron glazes, is a scourge almost as bad as slag, coke, and other "hot rocks".

The only solution I have really found, when I have had the opportunity to try it, is a machine that has auto-ground-tracking ground balance, such as a Tesoro Lobo SuperTraq, a Minelab Explorer, perhaps a Fisher Gold Bug 2, or something along those lines. 

Manual ground balance machines can handle it, but not as well, and it is tricky to keep fidgeting with the ground balance knob.   And pre-set ground balance... no good.

You might be able to mess with the Garrett a bit to eliminate some of the effect of the roofing tiles, but I'm really not familiar with that brand or model.  I would try adjusting its settings first, until it won't detect a piece of that stuff.  The interposing layer of clay rubble is probably going to be a challenge even for auto-track machines, because it is not a uniform distribution among the targets, but instead is "in the way" of the field.

Just my theorizing, late at night.   
Keep us posted on your progress!

HH,
R.I.

OK, to update regarding the search... Thus far, we have dug about 50 holes in response to "repeatable" signals which in almost every case seem to be from occasional "hot" bricks or tiles, or perhaps working somehow with salt from this near-beachfront site to create false yet repeatable signals. In fact, all work thus far has been done by breaking and removing concrete over each of the targets, and excavating through anywhere from six inches of concrete with brick or rubble base down to bare earth. Thus far, in almost every case after breaking out the concrete and excavating the lower layer of brick out of the hole, there was no further signal from the hole and the signal turned out to come from one of the brick pieces taken from the hole, or sometimes there has been no signal anywhere after excavating the hole and checking its contents thoroughly, so I assume salt led to false readings. I have tried using my Garrett SeaHunter in addition to the GTI 2500, but the "hot" bricks make that difficult. Since I have plenty of time and intend to dig all targets, I consider that so far we are doing things "right".... We're not leaving any holes behind that still emit signals.

Thus far, by spending at least several hours per day each time that we search (usually, one or two days per week) we have covered the interior patio/courtyard area, which is almost all concrete. We've also searched and excavated about half-a-dozen holes inside the former stable area. When the property was expanded beginning in 1799, the area along the original back wall of the courtyard (1680) was walled in and roofed over to form a stable. The reason for the old man's interest in searching this area first is that during the 1940s the old man's brother (then young, and using that old stable as a bedroom) saw a ghost in the form of a military officer dressed in old-time uniform appearing in his bedroom during the night, several times. Other guests reported seeing shadowy figures in the courtyard and hearing chains or other metalwork rattling in the room during the night.

Still, we didn't find anything (yet) after the first round of searching this room, and the courtyard, with the Garrett GTI 2500 using the 12-inch coil. I plan to come back around during the second phase of this project and use the double-box attachment while (1) notching out as exactly as I can this particular type of "hot" brick which are buried here, and (2) seeing if I can "ignore" the top six or eight inches of the search layer, to try to help avoid any remnants of these bricks left behind after the first round of searching.

After completing several old rooms lining the courtyard (i.e., original latrine area, original kitchen area, etc.) within the next couple of weeks, I then plan to move inside the main house. That's where things hopefully will become more interesting unless we first find something notable in the courtyard. Inside the house, the old man is convinced that there is a hidden sotano or basement under the "new" floor of the house, which dates to around 1799.

Also inside the house, i.e., under the floor inside the main house, is a reburial area containing human bones which I plan to avoid... As the story goes, sometime around 300 years ago the house (back then, just a fort with a log palisade around it) was sieged either by pirates or by Indians, depending on who's telling the story. Anyway, the besieged defenders were forced to bury their dead inside the fort, pretty much underfoot. Then sometime around 1799, as the story goes, the bones were disinterred when they were discovered to be "standing in the way of progress" in the location where the foundation for the new building was being constructed. The bones were packed into several wooden boxes and reburied inside the house under one of the front windows, in that particular location supposedly because it was near the same location where the bones had originally been discovered. Finally, the bones were said to have been disturbed once again during the 1930s when new water service required that tubes be placed under the floor of that room.

In any case, I plan to avoid that spot known to contain bones. I don't know whether it's a good sign or indifferent, but thus far we've found more evidence of indigenous culture in our diggings than evidence of Spanish-influenced culture. We've not found any valuable relics, yet we've found evidence of both indigenous and Spanish pottery, and unidentified iron pieces, small and very badly corroded, unrecognizable. I'm posting some pictures, including a photo of my good workman, Nelson, who is a treasure-hunter's ideal laborer... Here he is pictured after a ten-hour day of breaking concrete in ninety-degree heat, and he is still smiling...

EF

This is great and its good that you are including pictures.

Does the building have any columns? A part of a column could have a hollow place that could hold things. Out buildings around chicken houses or pig pins are good places to look to. See any old nails on the underside of limbs of any old trees? Sometimes they buried stuff under old tree limbs and used a plumb bob to hang form the nail to indicate where it was buried.

There are indeed brick structural columns at various points along the walls, mortared with a cement similar to modern Portland cement, yet without gravel-sized aggregates, just sand.  The wall plastering over the brick walls is what I call a caliche-type mixture which is reasonably durable, yet when used to plaster a wall, for example, it flakes very rapidly so that, for example, the old man paints his house every year with a "stucco-wash" containing paint, cemento blanco and sandy aggregate; most owners of old-finished walls re-coat at least some reasonable portion of it every few years, because the underlying layers of old cement used as stucco over the old bricks continues to flake away regularly.

The bricks were apparently home-made nearby and fired with varying consistency-- In some places under the flooring, the old bricks have turned to powder, while elsewhere they are very solid. In areas of walls exposed for many years to dripping rainwater, etc., these bricks round and soften sorta like bars of soap... They are solid up to a certain point, then the years of wet-and-dry cycles can make these bricks crumble easily.

The floors generally consist of a layer of "modern" concrete up to about a hundred years old, then below that is the layer of original brick flooring, which dates between the 1680 to 1799 period. Breaking through the floors has generally been easier than breaking through comparable thickness of modern concrete, although not because of reinforcing metal. There are certain areas where the old flooring concrete is amazing hard. Generally, though, the concrete used over the old flooring bricks is only about 100 years old, and of poor quality such that it forms a surface the local masons call "galletica" which translates as something like "saltine cracker" or something similarly thin and crispy, in English.

I haven't yet searched any walls. Thus far, only the exterior patio area and a couple of small rooms have been searched. I plan to search the walls carefully after completing the floors and foundations. I can already see that there will be many small iron nails and other hardware embedded in the walls. Because of the frequent cycle of wall re-plastering  (at least every few years), I am anticipating that there may be at least some "old" metal buried under more-recent wall layers... We'll see.

There are a couple of trees in the patio area-- One is a large tree with a high canopy where lives a wild parrot male, loud in the morning; the other tree is a large palm tree. Yet, both trees are certainly no more than 100 years old, from my guess. I checked around the base of both trees, and received a weak signal at the base of the palm. Perhaps it was lucky that it turned out to be a "hot" brick, since I'm leery of disturbing the roots of full-grown palms, after seeing the damage they cause when falling.

Thanks for your insight and comments.

EF

Don't be suprised to find out that this house has a Tunnel system underneath it.