DHM owns and operates five slate quarries in PA.

Slate and slate fill are excavated directly out of the ground and sold as a commodity directly to the public. As with all slate, the size of the pieces does vary. We do our very best to provide slate that is uniform in size although at times it may be difficult to accomplish. Our slate has many uses and is usually determined by the type.

PA2A
Size 2 inch topsize
Description

PA2A is a mixture of coarse stone and crushed stone dust, used as a road base or an under slab fill, will drain, has a structural coefficient, used where stability and drainability is a concern, primarily a clean material.

2RC/2A Modified
Size 1.5 inch topsize
Description

A mixture of coarse stone and fine material. Used as a road base and fill material. The fines in this material will be an earthen fine (dirt, silt, loam, clay). This material does not drain readily and has no structural coeffecient. Used where compaction and stability are a concern. Primarily a dirty material.

AASHTO #1
Size 4 inch topsize
Description

It is too bulky to be used as a surfacing material, however it makes an excellent stone for subgrade stabilization. Used for construction entrances and ditch lining and will not compact. It is a clean material.

AASHTO #3
Size 3 inch topsize
Description

This material is similar to AASHTO #1 but has a 3 inch topsize. It is also a bulky material but is somewhat easier to handle. It is used primarily in drainage situations. It is a clean material.

AASHTO #8 (1B’s)
Size ½ inch topsize
Description

This material has a ½ inch topsize. It is a clean material and will not compact. It is used for decorative purposes and walkways as well as one of the raw materials used to produce blacktop. It is also used as an Anti-skid material in some situations. Also used as a pipe bedding material in some situations.

AASHTO #10
Size 3/8 inch topsize
Description

This material is a crushed stone dust similar to the fines found in 2A. It has a 3/8 inch topsize and sizes down to a silt sized material. The material is used for pipe bedding and walkway areas. The material will not compact and drains slowly.

AASHTO #57 (2B’s)
Size 1 ½ inch topsize
Description

This material has a 1 ½ inch topsize. It is a clean material and sometimes used on driveways and walkways, because it gives an aesthetically please appearance. Also used as the primary raw aggregate in Ready Mixed Concrete and some Blacktop mixes. It will not compact.

AASHTO #67 (3/4 inch)
Size 3/4 inch
Description

Primarily a raw coarse aggregate used in the production of Ready Mixed Concrete and hot mixed Asphalt. This material is a minus one inch product with no fines. It is a clean material that can used for several purposes including driveways and walkways, although it will not compact in place. Other uses include drainage channels, swails and decorative purposes.

RIP RAP R4 to R8
Size 6 to 40 inches
Description

This material is the large boulder-sized rock that is often seen lining rivers and streams. Classified into six categories, R3 through R8, the material ranges in size from six inches to forty inches.  Although not often used by homeowners, the material makes an excellent flow barrier in situations where creeks, streams and rivers threaten property damage. Due to its size and nature, this material will not compact and is made to be machine placed in uniform layers.

Gabion Stone
Size Class A – 3 to 5 inch / Class B – 4 to 8 inch
Description

These materials are large blocky stones that are normally used to fill the Gabion baskets along roadways. These baskets make excellent retaining walls. Available in two sizes (Class A – 3 to 5 inch / Class B – 4 to 8 inch). They work very well for ditch lining in moderate flow areas. It is a clean material.

Anti-Skid
Size 1/2 inch or 3/8 inch topsize
Description

This material is the primary skid deterrent used by many state DOT’s and townships throughout the winter months. Several types and classifications of Anti Skid are in use in Pennsylvania, utilizing sands, limestone’s, slag and cinders. The material will not compact because it is meant to be applied in a loose condition. Most Anti Skids have a one half, or three eights inch topsize, and taper off to fine dust sized particles.

Sand
Size minus 3/8
Description

This material is the primary fine aggregate used in the production of Portland Cement Concrete. It is a minus three eights material that will not compact because of its particular shape. Produced only at specific plants, sand is sized into two specific classifications. Mason sand, used in the production of masonry grout, and concrete sand which is used to make Ready Mixed Concrete. Other uses include, golf course and recreational areas, beaches, and walkways and play areas.