A persistent virtual area that supports establishment of respective presences of communicants operating respective network nodes connected to the virtual area even after all network nodes have disconnected from the virtual area is maintained. A presence in the virtual area is established for a user of a Public Switched Telephone Network (PSTN) terminal device. Transmission of data associated with the virtual area to the PSTN terminal device.

A sand composition includes a carbonate sand present in an amount of 50 to 99.99% by weight, and a quartz sand in an amount of 0.01 to 50% by weight, each % based on a total weight of the sand composition. A cured specimen made from the sand composition has a compressive strength of 10 to 40 megapascal (MPa), and the compressive strength of the cured specimen is 10 to 90% greater than the compressive strength of a cured specimen made from a class G cement slurry.

A sand composition includes a carbonate sand present in an amount of 50 to 99.99% by weight, and a quartz sand in an amount of 0.01 to 50% by weight, each % based on a total weight of the sand composition. A cured specimen made from the sand composition has a compressive strength of 10 to 40 megapascal (MPa), and the compressive strength of the cured specimen is 10 to 90% greater than the compressive strength of a cured specimen made from a class G cement slurry.

A persistent virtual area that supports establishment of respective presences of communicants operating respective network nodes connected to the virtual area even after all network nodes have disconnected from the virtual area is maintained. A presence in the virtual area is established for a user of a Public Switched Telephone Network (PSTN) terminal device. Transmission of data associated with the virtual area to the PSTN terminal device.

A persistent virtual area that supports establishment of respective presences of communicants operating respective network nodes connected to the virtual area even after all network nodes have disconnected from the virtual area is maintained. A presence in the virtual area is established for a user of a Public Switched Telephone Network (PSTN) terminal device. Transmission of data associated with the virtual area to the PSTN terminal device.

A web browser interface for visualizing realtime network communications in spatial communication environments allows communicants to interact with other communicants in an immersive spatial communication environment without having to install any specialized communication software and without requiring special proxies or firewall additions or exceptions.

A web browser interface for visualizing realtime network communications in spatial communication environments allows communicants to interact with other communicants in an immersive spatial communication environment without having to install any specialized communication software and without requiring special proxies or firewall additions or exceptions.

A web browser interface for visualizing realtime network communications in spatial communication environments allows communicants to interact with other communicants in an immersive spatial communication environment without having to install any specialized communication software and without requiring special proxies or firewall additions or exceptions.

A web browser interface for visualizing realtime network communications in spatial communication environments allows communicants to interact with other communicants in an immersive spatial communication environment without having to install any specialized communication software and without requiring special proxies or firewall additions or exceptions.