It has not been analytically studied so the exact mineral is unknown. It is common and forms powdery masses associated with quartz and siderite. In many cases the chlorite is included in or replacing the quartz. Generally the process corrodes the quartz. Heavily pseudomorphed quartzes have been found but are poorly formed and not of particular interest. The northwest end of the pit is criss-crossed by several veins of pink dolomite visually identified only.
One series of pockets found in yielded some very interesting specimens. The pockets consisted of large quartz crystal fragments cemented together by dolomite with smaller amounts of pyrite, chalcopyrite, calcite, and barite. Perhaps the most interesting specimens found are hollow dolomite structures that appear to be epimorphs of calcite crystals.
The structures have crystallized, textured surfaces on both the exterior and interior of the structures. This suggests the dolomite continued to grow at least for a short time after the calcite was removed. Some show tiny second-generation calcites that have formed again on the interiors of the casts. Rare specimens have been found with delicate goethite needles growing out of the surface of red quartz crystals.
A very small amount of malachite has been found as an alteration product of chalcopyrite. Pyrite crystals are found in the northern end of the quarry associated with dolomite and calcite. They are tiny and not of interest on their own. Large contorted veins of white quartz run through the quarry. These frequently contain pockets with excellent specimens of quartz. The most notable quartz from Boylston is the hematized quartz.
Dustings of hematite, either on the surface or as a phantom, color many of the quartz crystals a beautiful orange color. Occasionally, bright red crystals can be found. Similar orange and red crystals are found at widespead locations around the world, but do not appear to be very common.
Another common variety, although less so than the hematized material, is when the crystals are being replaced by green chlorite. These occur in a wide degree of replacements, sometimes with very little of the original quartz crystal remaining. A few pieces with both orange and green on the same specimen have also been recovered, but generally it is either one or the other.
Many of the crystals at Boylston are highly distorted. Perhaps the most interesting are those that are flattened perpendicular to the prism axis.
These form excellent tabular and bladed crystals. In contrast, some other crystals at the locality are very long and thin - extended along the c-axis. These crystals are often curved. There is considerable evidence of geological activity in the rock. For instance, during the growth of the crystals, shock waves traveled through the rock. This is evident by the large number of crystals that are broken and partially rehealed.
In , at the northwest end of the pit opposite of where the orange crystals are found I recovered a pocket with several large crystals that were broken due to the shock waves. The crystals show evidence or regrowth or healing on the broken surfaces. Some or these surfaces were even overgrown by a thin layer of dolomite. These are quite interesting specimens that help in the understanding of the processes that took place at this locality. Other evidence of geological activity can be found at the southeast end of the quarry where orange Faden crystals have been found.
Faden is German for string and is the adopted term used to describe a quartz crystal or crystals with a white line running through them. The theory of development is that the Faden formed first, beginning as a simple grain of quartz. As a fissure in the rock opened up over time, the grain continued to break and reheal and reconnect, forming the Faden.
Finally at some latter point in time, quartz crystals grew around the Faden. This process is shown in the simple animation below. As the original grain was crystalline, the Faden is also crystalline and the angle of the final quartz crystals will match the crystallographic alignment of the original grain.
For instance, in the example shown below, the c-axis is actually horizontal. The crystal or crystals, depending on your definition have grown out from the Faden and into each other to form a single composite crystal. Many pockets at Boylston don't contain good crystals of quartz but rather rough stringy fingers of quartz. While it is purely speculation, these may be Fadens that were not overgrown with a later generation of clear quartz.
Their development into excellent mineral specimens may have been ended prematurely. Can't find what you're looking for? Suggest a New Listing for the guide or suggest edits by clicking " Suggest an Update" at the top of the listing. All suggestions are reviewed before posting. Park Technician; Email: david. Located between the communities of Boylston and Guysborough town , the park is an ideal place to camp while touring the Eastern Shore.
The wooded hilltop campground offers a spectacular view of Guysborough Harbour. When we're planning a trip, we like to check the following websites for sights, attractions and places to visit. Visit our Community Index for Nova Scotia. Unfortunately, we don't know of a website for Boylston.
If you can help, please contact us through our Feedback Page. Please keep in mind that we can not guarantee the accuracy or timeliness of the information on this website, so use with care. We encourage you to double-check the information that is critical to you. If you've found an error or have additional information that you would like to share, please don't hesitate to write. Click here to contact us. Around Boylston Mulgrave Jump to our Gazetteer entry for Mulgrave Mulgrave lies 10 miles [ Airports Near Boylston Websites We Enjoy Our population values for Boylston were taken from various sources and although they can be traced back to Statistics Canada StatCan , they should not be considered official.
A straight line distance ignores things like rivers, canyons, lakes, et cetera - it's truly a line drawn from Point A ie- Boylston to Point B. If you need the driving distance, we recommend that you use one of the Mapping Services listed on our Map Page for Boylston.
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