
The state seal was designed in 1910 while Alaska was a territory and not a state.
According to a pamphlet on the Boney Courthouse Artwork in the Alaska Court System:
In 1884 Congress provided for a civil government for Alaska, and the first governor “on his own motion” designed and had a seal made for the District of Alaska. The seal was used until 1910 when Governor Walter E. Clark said the seal placed too much emphasis on icebergs, northern lights, and native people. He had a draftsman in Juneau draw a rough draft of a new seal, which incorporated the original features plus symbols for mining, agriculture, fisheries, fur seal rookeries, and a railroad.
The design was approved by the Acting Attorney General of the United States. A “more refined” drawing was made by an unknown person in the Department of the Interior and the new seal was ready for use early in 1911. After Alaska was changed from a District to a Territory in 1912, the new designation was substituted on the seal. The Constitution for the State of Alaska (1959) provides that the Territorial Seal shall be the Seal for the State of Alaska, with the word “Territory” changed to that of “State.”
According to the office of the Lt Governor of Alaska:
The rays above the mountains represent the famous Alaskan northern lights, also known as aurora borealis. The smelter symbolizes mining, the train stands for Alaska’s rail transportation, and ships denote marine transportation. The trees symbolize Alaska’s wealth of timber and other forest products, and the farmer, his horse, and the three shocks of wheat portray Alaska’s agriculture. The fish and seals signify the importance of seafood to Alaska’s economy.
Although road and air transportation, oil and gas and tourism have developed considerably since the Seal was designed in 1910, Alaska’s State Seal still represents the vast wealth, economy and incredible natural setting of the forty-ninth State.
 
 
Symbols on the Alaska State Seal:
Alaska State Seal
This short, but concise history was put up by the office of Lieutenant Governor Loren Leman, and includes the various legislative conditions needed to use the seal.
Source: Office of Lieutenant Governor Loren Leman
Alaska State Seal (Symbolism)
This site gives an in depth explanation of the symbolism of Alaska’s golden state seal.
Source: John’s Alaska Railroad Page