Room and pillar (variant of breast stoping), also called pillar and stall, is a mining system in which the mined material is extracted across a horizontal plane, creating horizontal arrays of rooms and pillars. The ore is extracted in two phases. In the first, "pillars" of untouched material are left to support the roof overburden, and open areas or "rooms" are extracted underground; the pillars are then partially extracted in the same manner as in the "Board & Pillar method". The technique is usually used for relatively flat-lying deposits, such as those that follow a particular stratum.
The room and pillar system is used in mining coal, iron and base metals ores, particularly when found as manto or blanket deposits, stone and aggregates, talc, soda ash and potash.
History
Room and pillar mining is one of the oldest mining methods. Early room and pillar mines were developed more or less at random, with pillar sizes determined empirically and headings driven in whichever direction was convenient.
At this time it sounds like Wordpress is the top blogging platform available right now. (from what I've read) Is that what you are using on your blog? outlook 365 sign in
Steam rooms are worked for unwinding and as an amusement put. The room has planes that get the steam to the coveted temperatures. This is accomplished utilizing a controller settled in the place.outdoor sauna
You have a real ability for writing unique content. I like how you think and the way you represent your views in this article. I agree with your way of thinking. Thank you for sharing. training room rental
This is especially engaging since various sorts and levels of reverb can be tried out for a similar track. Thumps pressing the hardware and moving to another room just to check whether you like the reverb better. PVC ramen
ReplyDeleteAt this time it sounds like Wordpress is the top blogging platform available right now. (from what I've read) Is that what you are using on your blog? outlook 365 sign in
This comment has been removed by the author.
ReplyDeleteSteam rooms are worked for unwinding and as an amusement put. The room has planes that get the steam to the coveted temperatures. This is accomplished utilizing a controller settled in the place.outdoor sauna
ReplyDeleteThis blog is so rational. Left its readers stun.
ReplyDeleteteam building events southampton
how to find best related niche sites for guest posting
ReplyDeleteespn.com/activate
xfinity.com/authorize
You have a real ability for writing unique content. I like how you think and the way you represent your views in this article. I agree with your way of thinking. Thank you for sharing. training room rental
ReplyDeleteI got too much interesting stuff on your blog. I guess I am not the only one having all the enjoyment here! Keep up the good work. Trainingroomsg.com
ReplyDeleteThere are a lot of blogs over the Internet. But I can surely say that your blog is amazing in all. It has all the qualities that a perfect blog should have. www.trainingroomsg.com - training room rental Singapore
ReplyDeleteThat is really nice to hear. thank you for the update and good luck. BYDLENÍ
ReplyDeleteThis is especially engaging since various sorts and levels of reverb can be tried out for a similar track. Thumps pressing the hardware and moving to another room just to check whether you like the reverb better. PVC ramen
ReplyDelete